From: Will Deacon <will@kernel.org>
To: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
Will Deacon <will@kernel.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Marc Zyngier <maz@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Peter Zijlstra <peterz@infradead.org>,
Morten Rasmussen <morten.rasmussen@arm.com>,
Qais Yousef <qais.yousef@arm.com>,
Suren Baghdasaryan <surenb@google.com>,
Quentin Perret <qperret@google.com>, Tejun Heo <tj@kernel.org>,
Johannes Weiner <hannes@cmpxchg.org>,
Ingo Molnar <mingo@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
"Rafael J. Wysocki" <rjw@rjwysocki.net>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
Valentin Schneider <valentin.schneider@arm.com>,
Mark Rutland <mark.rutland@arm.com>,
kernel-team@android.com,
Valentin Schneider <Valentin.Schneider@arm.com>
Subject: [PATCH v11 05/16] sched: Reject CPU affinity changes based on task_cpu_possible_mask()
Date: Fri, 30 Jul 2021 12:24:32 +0100 [thread overview]
Message-ID: <20210730112443.23245-6-will@kernel.org> (raw)
In-Reply-To: <20210730112443.23245-1-will@kernel.org>
Reject explicit requests to change the affinity mask of a task via
set_cpus_allowed_ptr() if the requested mask is not a subset of the
mask returned by task_cpu_possible_mask(). This ensures that the
'cpus_mask' for a given task cannot contain CPUs which are incapable of
executing it, except in cases where the affinity is forced.
Reviewed-by: Valentin Schneider <Valentin.Schneider@arm.com>
Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
kernel/sched/core.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9fd598b8dac5..dbce9cd83a53 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2700,15 +2700,17 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
u32 flags)
{
const struct cpumask *cpu_valid_mask = cpu_active_mask;
+ const struct cpumask *cpu_allowed_mask = task_cpu_possible_mask(p);
unsigned int dest_cpu;
struct rq_flags rf;
struct rq *rq;
int ret = 0;
+ bool kthread = p->flags & PF_KTHREAD;
rq = task_rq_lock(p, &rf);
update_rq_clock(rq);
- if (p->flags & PF_KTHREAD || is_migration_disabled(p)) {
+ if (kthread || is_migration_disabled(p)) {
/*
* Kernel threads are allowed on online && !active CPUs,
* however, during cpu-hot-unplug, even these might get pushed
@@ -2722,6 +2724,11 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
cpu_valid_mask = cpu_online_mask;
}
+ if (!kthread && !cpumask_subset(new_mask, cpu_allowed_mask)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
/*
* Must re-check here, to close a race against __kthread_bind(),
* sched_setaffinity() is not guaranteed to observe the flag.
--
2.32.0.402.g57bb445576-goog
next prev parent reply other threads:[~2021-07-30 11:25 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-30 11:24 [PATCH v11 00/16] Add support for 32-bit tasks on asymmetric AArch32 systems Will Deacon
2021-07-30 11:24 ` [PATCH v11 01/16] sched: Introduce task_cpu_possible_mask() to limit fallback rq selection Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 02/16] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1 Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 03/16] cpuset: Honour task_cpu_possible_mask() in guarantee_online_cpus() Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 04/16] cpuset: Cleanup cpuset_cpus_allowed_fallback() use in select_fallback_rq() Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` Will Deacon [this message]
2021-08-23 9:26 ` [tip: sched/core] sched: Reject CPU affinity changes based on task_cpu_possible_mask() tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 06/16] sched: Introduce task_struct::user_cpus_ptr to track requested affinity Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 07/16] sched: Split the guts of sched_setaffinity() into a helper function Will Deacon
2021-08-17 15:40 ` Peter Zijlstra
2021-08-18 10:50 ` Will Deacon
2021-08-18 10:56 ` Peter Zijlstra
2021-08-18 11:11 ` Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 08/16] sched: Allow task CPU affinity to be restricted on asymmetric systems Will Deacon
2021-08-17 15:10 ` Peter Zijlstra
2021-08-18 10:42 ` Will Deacon
2021-08-18 10:56 ` Peter Zijlstra
2021-08-18 11:53 ` Peter Zijlstra
2021-08-18 12:19 ` Will Deacon
2021-08-18 11:06 ` Peter Zijlstra
2021-08-17 15:41 ` Peter Zijlstra
2021-08-18 10:43 ` Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 09/16] sched: Introduce dl_task_check_affinity() to check proposed affinity Will Deacon
2021-08-23 9:26 ` [tip: sched/core] " tip-bot2 for Will Deacon
2021-07-30 11:24 ` [PATCH v11 10/16] arm64: Implement task_cpu_possible_mask() Will Deacon
2021-07-30 11:24 ` [PATCH v11 11/16] arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0 Will Deacon
2021-07-30 11:24 ` [PATCH v11 12/16] arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system Will Deacon
2021-07-30 11:24 ` [PATCH v11 13/16] arm64: Advertise CPUs capable of running 32-bit applications in sysfs Will Deacon
2021-07-30 11:24 ` [PATCH v11 14/16] arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0 Will Deacon
2021-07-30 11:24 ` [PATCH v11 15/16] arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores Will Deacon
2021-07-30 11:24 ` [PATCH v11 16/16] Documentation: arm64: describe asymmetric 32-bit support Will Deacon
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