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lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Wed, Jan 28, 2026 at 10:23 AM Roman Gushchin <roman.gushchin@linux.dev> wrote: Works for me. Agree. That's the flexibility part that makes the whole thing worth while and the reason to do such oom policy as bpf progs. But something tangible and useful needs to be there from day one. systmed-oomd-like sounds very ...
{ "author": "Alexei Starovoitov <alexei.starovoitov@gmail.com>", "date": "Wed, 28 Jan 2026 10:53:50 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
Josh Don <joshdon@google.com> writes: Michal pointed at a more fundamental problem: if a bpf handler performed some actions (e.g. killed a program), how to safely allow other bpf handlers to exit without performing redundant destructive operations? Now it works on marking victim processes, so that subsequent kernel o...
{ "author": "Roman Gushchin <roman.gushchin@linux.dev>", "date": "Wed, 28 Jan 2026 11:03:16 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
Matt Bobrowski <mattbobrowski@google.com> writes: Yes. Idk, maybe (u64)-1 works better here, I don't have a strong opinion. Realistically I doubt there are too many bpf users with !CONFIG_CGROUPS. Alexei even suggested in the past to make CONFIG_MEMCG mandatory, which implies CONFIG_CGROUPS. I'll try, thanks! Idk...
{ "author": "Roman Gushchin <roman.gushchin@linux.dev>", "date": "Wed, 28 Jan 2026 11:18:36 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Mon, Jan 26, 2026 at 06:44:12PM -0800, Roman Gushchin wrote: If contended and we end up waiting here, some forward progress could have been made in the interim. Enough such that this pending OOM event initiated by the call into bpf_out_of_memory() may no longer even be warranted. What do you think about adding an e...
{ "author": "Matt Bobrowski <mattbobrowski@google.com>", "date": "Wed, 28 Jan 2026 20:21:54 +0000", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On 1/26/26 6:44 PM, Roman Gushchin wrote: [ ... ] iiuc, this will allow only one oom_ops to be attached to a cgroup. Considering oom_ops is the only user of the cgrp->bpf.struct_ops_links (added in patch 2), the list should have only one element for now. Copy some context from the patch 2 commit log. > This chan...
{ "author": "Martin KaFai Lau <martin.lau@linux.dev>", "date": "Thu, 29 Jan 2026 13:00:11 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
Martin KaFai Lau <martin.lau@linux.dev> writes: Hi Martin! Sorry, I'm not quite sure what do you mean, can you please elaborate more? We decided (in conversations at LPC) that 1 bpf oom policy for memcg is good for now (with a potential to extend in the future, if there will be use cases). But it seems like there i...
{ "author": "Roman Gushchin <roman.gushchin@linux.dev>", "date": "Fri, 30 Jan 2026 15:29:31 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Wed, Jan 28, 2026 at 08:59:34AM -0800, Alexei Starovoitov wrote: For the auto-loading capability you speak of here, I'm currently interpreting it as being some form of conceptually similar extension to the BPF preload functionality. Have I understood this correctly? If so, I feel as though something like this would...
{ "author": "Matt Bobrowski <mattbobrowski@google.com>", "date": "Mon, 2 Feb 2026 03:26:07 +0000", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Mon, Jan 26, 2026 at 06:44:09PM -0800, Roman Gushchin wrote: This code has been changed in the mm-tree and you can directly use mem_cgroup_get_from_id() after changes in the mm-tree.
{ "author": "Shakeel Butt <shakeel.butt@linux.dev>", "date": "Sun, 1 Feb 2026 19:50:48 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Tue, Jan 27, 2026 at 09:12:56PM +0000, Roman Gushchin wrote: Yes, please, this is something that I had mentioned to you the other day too. With this kind of BPF kfunc, we'll basically be able to handle memcg scoped OOM events inline without necessarily being forced to kill off anything.
{ "author": "Matt Bobrowski <mattbobrowski@google.com>", "date": "Mon, 2 Feb 2026 04:06:32 +0000", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Mon, Jan 26, 2026 at 06:44:11PM -0800, Roman Gushchin wrote: task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN is also representative of an unkillable task, so why not fold this up into the above conditional? Also, why not bother checking states like mm_flags_test(MMF_OOM_SKIP, task->mm) and in_vfork() here too? In...
{ "author": "Matt Bobrowski <mattbobrowski@google.com>", "date": "Mon, 2 Feb 2026 04:49:09 +0000", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Mon, Jan 26, 2026 at 06:44:08PM -0800, Roman Gushchin wrote: This is fine. Feel free to add: Acked-by: Matt Bobrowski <mattbobrowski@google.com>
{ "author": "Matt Bobrowski <mattbobrowski@google.com>", "date": "Mon, 2 Feb 2026 04:56:57 +0000", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Mon, Jan 26, 2026 at 06:44:13PM -0800, Roman Gushchin wrote: Why not just do a direct memory read (i.e., task->signal->oom_mm) within the BPF program? I'm not quite convinced that a BPF kfunc wrapper for something like tsk_is_oom_victim() is warranted as you can literally achieve the same semantics without one.
{ "author": "Matt Bobrowski <mattbobrowski@google.com>", "date": "Mon, 2 Feb 2026 05:39:48 +0000", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Sun, Feb 1, 2026 at 9:39 PM Matt Bobrowski <mattbobrowski@google.com> wrote: +1 there is no need for this kfunc.
{ "author": "Alexei Starovoitov <alexei.starovoitov@gmail.com>", "date": "Mon, 2 Feb 2026 09:30:23 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH bpf-next v3 00/17] mm: BPF OOM
This patchset adds an ability to customize the out of memory handling using bpf. It focuses on two parts: 1) OOM handling policy, 2) PSI-based OOM invocation. The idea to use bpf for customizing the OOM handling is not new, but unlike the previous proposal [1], which augmented the existing task ranking policy, this o...
On Sun, Feb 1, 2026 at 7:26 PM Matt Bobrowski <mattbobrowski@google.com> wrote: It's not a hard prerequisite, but it has to be thought through. bpf side is ready today. bpf preload is an example of it. The oom side needs to design an interface to do it. sysctl to enable builtin bpf-oom policy is probably too rigid. Ma...
{ "author": "Alexei Starovoitov <alexei.starovoitov@gmail.com>", "date": "Mon, 2 Feb 2026 09:50:05 -0800", "thread_id": "CAADnVQL3+huSAwoYRexoSDaLRK+nEsY6UUnVSmhk_sGYUYsO7Q@mail.gmail.com.mbox.gz" }
lkml
[PATCH v6 0/4] memory: tegra: Add MC error logging support for Tegra264 SoC
In Tegra264, different components from memory subsystems like Memory Controller Fabric (MCF), HUB, HUB Common (HUBC), Side Band Shim (SBS) and MC Channels have different interrupt lines for receiving memory controller error interrupts. This patch set includes changes to add support and enable Memory Controller error lo...
Group MC error related registers into a struct as they could have SoC specific values. Tegra264 has different register offsets than the existing devices and so in order to add support for Tegra264 we need to first make this change. Signed-off-by: Ketan Patil <ketanp@nvidia.com> --- drivers/memory/tegra/mc.c | 4...
{ "author": "Ketan Patil <ketanp@nvidia.com>", "date": "Fri, 30 Jan 2026 17:30:52 +0000", "thread_id": "fa87cec4-1aa8-4e9b-9baa-8b543d2b7c6f@nvidia.com.mbox.gz" }
lkml
[PATCH v6 0/4] memory: tegra: Add MC error logging support for Tegra264 SoC
In Tegra264, different components from memory subsystems like Memory Controller Fabric (MCF), HUB, HUB Common (HUBC), Side Band Shim (SBS) and MC Channels have different interrupt lines for receiving memory controller error interrupts. This patch set includes changes to add support and enable Memory Controller error lo...
The current register definitions are not in sorted order. Sort these registers according to their address. Put bit fields and masks of the corresponding registers below the register definitions to clearly identify which fields belongs to which registers. Signed-off-by: Ketan Patil <ketanp@nvidia.com> --- drivers/memo...
{ "author": "Ketan Patil <ketanp@nvidia.com>", "date": "Fri, 30 Jan 2026 17:30:53 +0000", "thread_id": "fa87cec4-1aa8-4e9b-9baa-8b543d2b7c6f@nvidia.com.mbox.gz" }
lkml
[PATCH v6 0/4] memory: tegra: Add MC error logging support for Tegra264 SoC
In Tegra264, different components from memory subsystems like Memory Controller Fabric (MCF), HUB, HUB Common (HUBC), Side Band Shim (SBS) and MC Channels have different interrupt lines for receiving memory controller error interrupts. This patch set includes changes to add support and enable Memory Controller error lo...
Add support to handle multiple MC interrupts lines, as supported by Tegra264. Turn the single IRQ handler callback into a counted array to allow specifying a separate handler for each interrupt. Signed-off-by: Ketan Patil <ketanp@nvidia.com> --- drivers/memory/tegra/mc.c | 34 +++++++++++++++++++++------------ ...
{ "author": "Ketan Patil <ketanp@nvidia.com>", "date": "Fri, 30 Jan 2026 17:30:54 +0000", "thread_id": "fa87cec4-1aa8-4e9b-9baa-8b543d2b7c6f@nvidia.com.mbox.gz" }
lkml
[PATCH v6 0/4] memory: tegra: Add MC error logging support for Tegra264 SoC
In Tegra264, different components from memory subsystems like Memory Controller Fabric (MCF), HUB, HUB Common (HUBC), Side Band Shim (SBS) and MC Channels have different interrupt lines for receiving memory controller error interrupts. This patch set includes changes to add support and enable Memory Controller error lo...
In Tegra264, different components from memory subsystems like Memory Controller Fabric (MCF), HUB, HUB Common (HUBC), Side Band Shim (SBS) and channels have different interrupt lines for receiving memory controller error interrupts. Add support for logging memory controller errors on Tegra264. - Add MC error handling ...
{ "author": "Ketan Patil <ketanp@nvidia.com>", "date": "Fri, 30 Jan 2026 17:30:55 +0000", "thread_id": "fa87cec4-1aa8-4e9b-9baa-8b543d2b7c6f@nvidia.com.mbox.gz" }
lkml
[PATCH v6 0/4] memory: tegra: Add MC error logging support for Tegra264 SoC
In Tegra264, different components from memory subsystems like Memory Controller Fabric (MCF), HUB, HUB Common (HUBC), Side Band Shim (SBS) and MC Channels have different interrupt lines for receiving memory controller error interrupts. This patch set includes changes to add support and enable Memory Controller error lo...
On 30/01/2026 17:30, Ketan Patil wrote: For the series ... Reviewed-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Thanks Jon -- nvpublic
{ "author": "Jon Hunter <jonathanh@nvidia.com>", "date": "Mon, 2 Feb 2026 16:25:15 +0000", "thread_id": "fa87cec4-1aa8-4e9b-9baa-8b543d2b7c6f@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> ./drivers/resctrl/mpam_internal.h: linux/srcu.h is included more than once. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reported-by: Abaci Robot <abaci@linux.alibaba.com> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=27328 Signed-off-by: J...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:28 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
In the test__props_mismatch() kunit test we rely on the struct mpam_props being packed to ensure memcmp doesn't consider packing. Making it packed reduces the alignment of the features bitmap and so breaks a requirement for the use of atomics. As we don't rely on the set/clear of these bits being atomic, just make them...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:29 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
The MPAMSM_EL1 register determines the MPAM configuration for an SMCU. Add the register definition. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- arch/arm64/tools/sysreg | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm64/tools/sysreg...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:30 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
When kvm enables or disables MPAM traps to EL2 it clears all other bits in MPAM2_EL2. Notably, it clears the partition ids (PARTIDs) and performance monitoring groups (PMGs). Avoid changing these bits in anticipation of adding support for MPAM in the kernel. Otherwise, on a VHE system with the host running at EL2 wher...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:31 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
The MPAMSM_EL1 controls the MPAM labeling for an SMCU, Streaming Mode Compute Unit. As there is on MPAM support in kvm, make sure MPAMSM_EL1 accesses trigger an UNDEF. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- Changes since v2: Remove paragraph from ...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:32 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> MPAM allows traffic in the SoC to be labeled by the OS, these labels are used to apply policy in caches and bandwidth regulators, and to monitor traffic in the SoC. The label is made up of a PARTID and PMG value. The x86 equivalent calls these CLOSID and RMID, but they don't map...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:33 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Now that the MPAM system registers are expected to have values that change, reprogram them based on the previous value when a CPU is brought online. Previously MPAM's 'default PARTID' of 0 was always used for MPAM in kernel-space as this is the PARTID that hardware guarantees t...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:34 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Requestors need to populate the MPAM fields for any traffic they send on the interconnect. For the CPUs these values are taken from the corresponding MPAMy_ELx register. Each requestor may have a limit on the largest PARTID or PMG value that can be used. The MPAM driver has to d...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:35 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> The MPAM system registers will be lost if the CPU is reset during PSCI's CPU_SUSPEND. Add a PM notifier to restore them. mpam_thread_switch(current) can't be used as this won't make any changes if the in-memory copy says the register already has the correct value. In reality t...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:36 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
The MPAMSM_EL1 sets the MPAM labels, PMG and PARTID, for loads and stores generated by a shared SMCU. Disable the traps so the kernel can use it and set it to the same configuration as the per-EL cpu MPAM configuration. If an SMCU is not shared with other cpus then it is implementation defined whether the configuratio...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:37 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Care must be taken when modifying the PARTID and PMG of a task in any per-task structure as writing these values may race with the task being scheduled in, and reading the modified values. Add helpers to set the task properties, and the CPU default value. These use WRITE_ONCE(...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:38 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> While we trap the guest's attempts to read/write the MPAM control registers, the hardware continues to use them. Guest-EL0 uses KVM's user-space's configuration, as the value is left in the register, and guest-EL1 uses either the host kernel's configuration, or in the case of VH...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:39 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On nVHE systems whether or not MPAM is enabled, EL2 continues to use partid-0 for hypercalls, even when the host may have configured its kernel threads to use a different partid. 0 may have been assigned to another task. Copy the EL1 MPAM register to EL2. This ensures hypercalls use the same partid as the kernel thread...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:40 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl has its own data structures to describe its resources. We can't use these directly as we play tricks with the 'MBA' resource, picking the MPAM controls or monitors that best apply. We may export the same component as both L3 and MBA. Add mpam_resctrl_exports[] as the ar...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:41 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl documents that the domains appear in numeric order in the schemata file. This means a little more work is needed when bringing a domain online. Add the support for this, using resctrl_find_domain() to find the point to insert in the list. Reviewed-by: Jonathan Cameron ...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:42 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Systems with MPAM support may have a variety of control types at any point of their system layout. We can only expose certain types of control, and only if they exist at particular locations. Start with the well-known caches. These have to be depth 2 or 3 and support MPAM's cac...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:43 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> We already have a helper for resetting an mpam class and component. Hook it up to resctrl_arch_reset_all_ctrls() and the domain offline path. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- Changes since v2: Don't expose unlo...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:44 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Implement resctrl_arch_get_config() by testing the live configuration for a CPOR bitmap. For any other configuration type return the default. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Ben Horgan <...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:45 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl has two helpers for updating the configuration. resctrl_arch_update_one() updates a single value, and is used by the software-controller to apply feedback to the bandwidth controls, it has to be called on one of the CPUs in the resctrl:domain. resctrl_arch_update_domain...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:46 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> arm64 provides helpers for changing a task's and a cpu's mpam partid/pmg values. These are used to back a number of resctrl_arch_ functions. Connect them up. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:47 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Intel RDT's CDP feature allows the cache to use a different control value depending on whether the accesses was for instruction fetch or a data access. MPAM's equivalent feature is the other way up: the CPU assigns a different partid label to traffic depending on whether it was ...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:48 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Dave Martin <Dave.Martin@arm.com> MPAM uses a fixed-point formats for some hardware controls. Resctrl provides the bandwidth controls as a percentage. Add helpers to convert between these. Ensure bwa_wd is at most 16 to make it clear higher values have no meaning. Reviewed-by: Jonathan Cameron <jonathan.camer...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:49 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Dave Martin <Dave.Martin@arm.com> resctrl specifies the format of the control schemes, and these don't match the hardware. Some of the conversions are a bit hairy - add some kunit tests. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> [morse: squashe...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:50 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Because MPAM's pmg aren't identical to RDT's rmid, resctrl handles some data structures by index. This allows x86 to map indexes to RMID, and MPAM to map them to partid-and-pmg. Add the helpers to do this. Suggested-by: James Morse <james.morse@arm.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- Changes since...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:51 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
As MPAM's pmg are scoped by partid and RDT's rmid are global the rescrl mapping to an index needs to differ. Add some tests for the MPAM rmid mapping. Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- drivers/resctrl/test_mpam_resctrl.c | 49 +++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --gi...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:52 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
In order to calculate the rmid realloc threshold the size of the cache needs to be known. Cache domains will also be named after the cache id. So that this information can be extracted from cacheinfo we need to wait for it to be ready. The cacheinfo information is populated in device_initcall() so we wait for that. Si...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:53 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl supports 'MB', as a percentage throttling of traffic somewhere after the L3. This is the control that mba_sc uses, so ideally the class chosen should be as close as possible to the counters used for mba_local. MB's percentage control should be backed either with the fix...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:54 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl exposes a counter via a file named llc_occupancy. This isn't really a counter as its value goes up and down, this is a snapshot of the cache storage usage monitor. Add some picking code to find a cache as close as possible to the L3 that supports the CSU monitor. If th...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:55 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl has two types of counters, NUMA-local and global. MPAM has only bandwidth counters, but the position of the MSC may mean it counts NUMA-local, or global traffic. But the topology information is not available. Apply a heuristic: the L2 or L3 supports bandwidth monitors,...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:56 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> When there are enough monitors, the resctrl mbm local and total files can be exposed. These need all the monitors that resctrl may use to be allocated up front. Add helpers to do this. If a different candidate class is discovered, the old array should be free'd and the allocat...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:57 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> When there are not enough monitors, MPAM is able to emulate ABMC by making a smaller number of monitors assignable. These monitors still need to be allocated from the driver, and mapped to whichever control/monitor group resctrl wants to use them with. Add a second array to hol...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:58 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> ABMC exposes a fun corner case where a platform with one monitor can use ABMC for assignable counters - but not when CDP is enabled. Add some tests. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- drivers/resctrl/test_mpam_r...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:58:59 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> ABMC has a helper resctrl_arch_config_cntr() for changing the mapping between 'cntr_id' and a CLOSID/RMID pair. Add the helper. For MPAM this is done by updating the mon->mbwu_idx_to_mon[] array, and as usual CDP means it needs doing in three different ways. Reviewed-by: Jona...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:00 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> When resctrl wants to read a domain's 'QOS_L3_OCCUP', it needs to allocate a monitor on the corresponding resource. Monitors are allocated by class instead of component. MBM monitors are much more complicated, if there are enough monitors, they will be pre-allocated and free-ru...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:01 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl uses resctrl_arch_rmid_read() to read counters. CDP emulation means the counter may need reading in three different ways. The same goes for reset. The helpers behind the resctrl_arch_ functions will be re-used for the ABMC equivalent functions. Add the rounding helper ...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:02 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> When used in ABMC mode, resctrl uses a different set of helpers to read and reset the counters. Add these. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- drivers/r...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:03 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> resctrl's limbo code needs to be told when the data left in a cache is small enough for the partid+pmg value to be re-allocated. x86 uses the cache size divided by the number of rmid users the cache may have. Do the same, but for the smallest cache, and with the number of parti...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:04 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> A few resctrl features and hooks need to be provided, but aren't needed or supported on MPAM platforms. resctrl has individual hooks to separately enable and disable the closid/partid and rmid/pmg context switching code. For MPAM this is all the same thing, as the value in stru...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:05 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Enough MPAM support is present to enable ARCH_HAS_CPU_RESCTRL. Let it rip^Wlink! ARCH_HAS_CPU_RESCTRL indicates resctrl can be enabled. It is enabled by the arch code simply because it has 'arch' in its name. This removes ARM_CPU_RESCTRL as a mimic of X86_CPU_RESCTRL. While ...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:06 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> Now that MPAM links against resctrl, call resctrl_init() to register the filesystem and setup resctrl's structures. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- Ch...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:07 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> MPAM supports a minimum and maximum control for memory bandwidth. The purpose of the minimum control is to give priority to tasks that are below their minimum value. Resctrl only provides one value for the bandwidth configuration, which is used for the maximum. The minimum cont...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:08 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
By default we generate a minimum bandwidth value that is 5% lower than the maximum bandwidth value given by resctrl. Add a test for this. Signed-off-by: James Morse <james.morse@arm.com> [horgan: Split test into separate patch] Signed-off-by: Ben Horgan <ben.horgan@arm.com> --- drivers/resctrl/test_mpam_devices.c | ...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:09 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Shanker Donthineni <sdonthineni@nvidia.com> The MPAM specification includes the MPAMF_IIDR, which serves to uniquely identify the MSC implementation through a combination of implementer details, product ID, variant, and revision. Certain hardware issues/errata can be resolved using software workarounds. Introdu...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:10 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Shanker Donthineni <sdonthineni@nvidia.com> The MPAM bandwidth partitioning controls will not be correctly configured, and hardware will retain default configuration register values, meaning generally that bandwidth will remain unprovisioned. To address the issue, follow the below steps after updating the MBW_M...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:11 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Shanker Donthineni <sdonthineni@nvidia.com> In the T241 implementation of memory-bandwidth partitioning, in the absence of contention for bandwidth, the minimum bandwidth setting can affect the amount of achieved bandwidth. Specifically, the achieved bandwidth in the absence of contention can settle to any value...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:12 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: Shanker Donthineni <sdonthineni@nvidia.com> The registers MSMON_MBWU_L and MSMON_MBWU return the number of requests rather than the number of bytes transferred. Bandwidth resource monitoring is performed at the last level cache, where each request arrive in 64Byte granularity. The current implementation returns...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:13 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
From: James Morse <james.morse@arm.com> CMN-650 is afflicted with an erratum where the CSU NRDY bit never clears. This tells us the monitor never finishes scanning the cache. The erratum document says to wait the maximum time, then ignore the field. Add a flag to indicate whether this is the final attempt to read the...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Mon, 12 Jan 2026 16:59:14 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/12/26 08:58, Ben Horgan wrote: Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Thanks. -Fenghua
{ "author": "Fenghua Yu <fenghuay@nvidia.com>", "date": "Mon, 12 Jan 2026 09:13:24 -0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:39 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 14:19:16 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:40 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> nvhe
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 14:21:04 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Jonathan, On 1/13/26 14:21, Jonathan Cameron wrote: In this case, I do mean arm64_sw.hvhe which is the configuration when kvm-arm.mode=protected. The aliasing of the registers when E2H is set meant that the read_sysreg_s(SYS_MPAM1_EL1) was actually accessing SYS_MPAM2_EL2 and so the read and write were for the sam...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Tue, 13 Jan 2026 14:35:16 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:44 +0000 Ben Horgan <ben.horgan@arm.com> wrote: There was a question from Zhengheng on v2 that doesn't seem to be addressed and I'm not seeing a reply on list. Maybe an email snafu? https://lore.kernel.org/all/20260109034506.1176234-1-zengheng4@huawei.com/ Please +CC zhengheng on future v...
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 14:46:35 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:51 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Much easier to read. Thanks! Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 14:55:40 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Jonathan, Zeng, On 1/13/26 14:46, Jonathan Cameron wrote: Yes, sorry! For some reason I don't get his emails. :( It happened on the base mpam driver series too. I'll keep a better look at lore and reply to his v2 query. Will do. Should be CC'd on this version too. I don't if there is an email issue with that too...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Tue, 13 Jan 2026 14:58:41 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:52 +0000 Ben Horgan <ben.horgan@arm.com> wrote: I'm not sure this particular test brings a massive amount of value, but I'm not one to object to more tests! Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 14:59:55 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:53 +0000 Ben Horgan <ben.horgan@arm.com> wrote: I don't mind the patch but I'm not entirely following this comment. Is the point that previously there was a sneaky user before this was added in the series? Anyhow, that's not in the patch itself so Reviewed-by: Jonathan Cameron <jonathan.cam...
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 15:01:59 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:54 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 15:06:18 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:57 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 15:10:25 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Jonathan, On 1/13/26 15:01, Jonathan Cameron wrote: Yes, arm_mpam: resctrl: Add support for 'MB' resource, accesses cacheinfo so wanted to order this patch before that. Thanks, Ben
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Tue, 13 Jan 2026 15:15:43 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:59 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 15:26:38 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:59:08 +0000 Ben Horgan <ben.horgan@arm.com> wrote: I'm interested to see how this plays out as a default choice vs what people elect to run. Seems harmless to start with this. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 15:39:38 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:59:09 +0000 Ben Horgan <ben.horgan@arm.com> wrote: Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
{ "author": "Jonathan Cameron <jonathan.cameron@huawei.com>", "date": "Tue, 13 Jan 2026 15:43:36 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Ben, (Please note I am unfamiliar with this code so missing some context.) On 1/12/26 8:58 AM, Ben Horgan wrote: It should not be necessary to offline the control domain if attempt to online it failed but removing it from the ctrl_domains list is necessary. What happens to memory dom points to? This error path ...
{ "author": "Reinette Chatre <reinette.chatre@intel.com>", "date": "Tue, 13 Jan 2026 08:49:29 -0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Ben, On 1/12/26 8:58 AM, Ben Horgan wrote: fyi ... [1] enabled total memory bandwidth to also be used as input to software controller and additionally enabled user space to set per resource group which memory bandwidth event is used as input to the software controller. Reinette [1] https://lore.kernel.org/all/20...
{ "author": "Reinette Chatre <reinette.chatre@intel.com>", "date": "Tue, 13 Jan 2026 14:18:48 -0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Ben, On 1/12/26 8:58 AM, Ben Horgan wrote: Reading the above loop and how it is used to call mpam_resctrl_monitor_init() for every event it looks like there is an implicit assumption that MPAM supports all events known to resctrl. Please consider the most recent resctrl feature "telemetry monitoring" currently qu...
{ "author": "Reinette Chatre <reinette.chatre@intel.com>", "date": "Tue, 13 Jan 2026 15:14:29 -0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Another advantage is that, given the small size of the L2 cache, frequent switching of MPAM configurations between kernel and user modes can cause cache-capacity jitter, making it difficult to isolate interference from noisy neighborhood. However, in addition to the issues mentioned above, updating the MPAM1_EL1 confi...
{ "author": "Zeng Heng <zengheng4@huawei.com>", "date": "Wed, 14 Jan 2026 14:51:49 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:39 +0000, Ben Horgan <ben.horgan@arm.com> wrote: What's the rationale for doing this independently of rest of the MPAM stuff in __activate_traps_mpam()? M. -- Without deviation from the norm, progress is not possible.
{ "author": "Marc Zyngier <maz@kernel.org>", "date": "Wed, 14 Jan 2026 12:06:28 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Mon, 12 Jan 2026 16:58:40 +0000, Ben Horgan <ben.horgan@arm.com> wrote: Is it really OK to not preserve the rest of MPAM2_EL2? This explicitly clears MPAM2_EL2.MPAMEN, which feels counter-productive. M. -- Without deviation from the norm, progress is not possible.
{ "author": "Marc Zyngier <maz@kernel.org>", "date": "Wed, 14 Jan 2026 12:09:14 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Marc, On 1/14/26 12:09, Marc Zyngier wrote: There are 3 things to consider: 1. traps - these are only relevant when we leave EL2 and are dealt with in __activate_traps_mpam(). (This also covers EnMPAMSM which is a not-trap bit.) 2. MPAM2_EL2.MPAMEN - this is read only as long as we have an EL3 and if we don't have...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Wed, 14 Jan 2026 14:39:58 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Marc, On 1/14/26 12:06, Marc Zyngier wrote: The __activate_traps_mpam() is relevant even for nvhe but __mpam_guest_load() is only need in vhe as otherwise we can rely on MPAM1_EL1 and MPAM0_EL0 having the same partid/pmg configuration (although this MPAM policy will likely become configurable sometime down the lin...
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Wed, 14 Jan 2026 14:50:22 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Marc, On 1/14/26 14:39, Ben Horgan wrote: As discussed offline, to avoid having to reason about MPAM2_EL2.MPAMEN I'll set this bit to 1 in this write as we are already assuming mpam is enabled and we want to keep it enabled. Thanks, Ben
{ "author": "Ben Horgan <ben.horgan@arm.com>", "date": "Wed, 14 Jan 2026 16:50:50 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Wed, 14 Jan 2026 16:50:50 +0000, Ben Horgan <ben.horgan@arm.com> wrote: Sounds good, thanks. M. -- Without deviation from the norm, progress is not possible.
{ "author": "Marc Zyngier <maz@kernel.org>", "date": "Wed, 14 Jan 2026 17:50:26 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/13/26 12:58 AM, Ben Horgan wrote: Reviewed-by: Gavin Shan <gshan@redhat.com>
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 10:12:57 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/13/26 12:58 AM, Ben Horgan wrote: Reviewed-by: Gavin Shan <gshan@redhat.com>
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 10:14:48 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/13/26 12:58 AM, Ben Horgan wrote: Reviewed-by: Gavin Shan <gshan@redhat.com>
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 10:16:08 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/13/26 12:58 AM, Ben Horgan wrote: Reviewed-by: Gavin Shan <gshan@redhat.com>
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 10:33:33 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/13/26 12:58 AM, Ben Horgan wrote: Reviewed-by: Gavin Shan <gshan@redhat.com>
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 10:34:32 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hi Ben, On 1/13/26 12:58 AM, Ben Horgan wrote: With the following nitpick addressed: Reviewed-by: Gavin Shan <gshan@redhat.com> Nitpick: Needn't include those two header files since they have been included to <asm/mpam.h> Thanks, Gavin
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 14:47:28 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On 1/13/26 12:58 AM, Ben Horgan wrote: Reviewed-by: Gavin Shan <gshan@redhat.com>
{ "author": "Gavin Shan <gshan@redhat.com>", "date": "Thu, 15 Jan 2026 14:50:08 +0800", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
On Wed, 14 Jan 2026 14:50:22 +0000, Ben Horgan <ben.horgan@arm.com> wrote: It is completely unclear to me what enforces this. Please point me to the code that does that. Or not. the VM only exists as an extension of userspace, and I don't see on what grounds it should get its own MPAM configuration. I don't care a...
{ "author": "Marc Zyngier <maz@kernel.org>", "date": "Thu, 15 Jan 2026 09:05:28 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }
lkml
[PATCH v3 00/47] arm_mpam: Add KVM/arm64 and resctrl glue code
This new version of the mpam missing pieces has no major rework from the previous version. It's mainly small corrections and code tidying based on review and things I spotted along the way. To be able to merge this we need review from more people and people to start testing on their platforms and giving some Tested-by ...
Hello Ben, Shouldn't it be return -EOPNOTSUPP;? However, before the function update_rmid_limits() is called, there is a check: if (cache_has_usable_csu(class) && topology_matches_l3(class)). cache_has_usable_csu(class) already contains an identical check. Therefore, I think it's safe to remove this redundant one. B...
{ "author": "\"Shaopeng Tan (Fujitsu)\" <tan.shaopeng@fujitsu.com>", "date": "Thu, 15 Jan 2026 10:05:49 +0000", "thread_id": "ca45ea06-53fa-4010-86c6-66213243b636@nvidia.com.mbox.gz" }