May 2025 - Linux-stable-mirror

FAILED: patch "[PATCH] cpufreq/sched: Explicitly synchronize limits_changed flag" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 79443a7e9da3c9f68290a8653837e23aba0fa89f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042156-uncurled-citizen-ae9a@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 79443a7e9da3c9f68290a8653837e23aba0fa89f Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" <rafael.j.wysocki(a)intel.com> Date: Tue, 15 Apr 2025 11:59:15 +0200 Subject: [PATCH] cpufreq/sched: Explicitly synchronize limits_changed flag handling The handling of the limits_changed flag in struct sugov_policy needs to be explicitly synchronized to ensure that cpufreq policy limits updates will not be missed in some cases. Without that synchronization it is theoretically possible that the limits_changed update in sugov_should_update_freq() will be reordered with respect to the reads of the policy limits in cpufreq_driver_resolve_freq() and in that case, if the limits_changed update in sugov_limits() clobbers the one in sugov_should_update_freq(), the new policy limits may not take effect for a long time. Likewise, the limits_changed update in sugov_limits() may theoretically get reordered with respect to the updates of the policy limits in cpufreq_set_policy() and if sugov_should_update_freq() runs between them, the policy limits change may be missed. To ensure that the above situations will not take place, add memory barriers preventing the reordering in question from taking place and add READ_ONCE() and WRITE_ONCE() annotations around all of the limits_changed flag updates to prevent the compiler from messing up with that code. Fixes: 600f5badb78c ("cpufreq: schedutil: Don't skip freq update when limits change") Cc: 5.3+ <stable(a)vger.kernel.org> # 5.3+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Reviewed-by: Christian Loehle <christian.loehle(a)arm.com> Link: https://patch.msgid.link/3376719.44csPzL39Z@rjwysocki.net diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index b713ce0a5702..bcab867575bb 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -81,9 +81,20 @@ static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) if (!cpufreq_this_cpu_can_update(sg_policy->policy)) return false; - if (unlikely(sg_policy->limits_changed)) { - sg_policy->limits_changed = false; + if (unlikely(READ_ONCE(sg_policy->limits_changed))) { + WRITE_ONCE(sg_policy->limits_changed, false); sg_policy->need_freq_update = true; + + /* + * The above limits_changed update must occur before the reads + * of policy limits in cpufreq_driver_resolve_freq() or a policy + * limits update might be missed, so use a memory barrier to + * ensure it. + * + * This pairs with the write memory barrier in sugov_limits(). + */ + smp_mb(); + return true; } @@ -377,7 +388,7 @@ static inline bool sugov_hold_freq(struct sugov_cpu *sg_cpu) { return false; } static inline void ignore_dl_rate_limit(struct sugov_cpu *sg_cpu) { if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_min) - sg_cpu->sg_policy->limits_changed = true; + WRITE_ONCE(sg_cpu->sg_policy->limits_changed, true); } static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu, @@ -883,7 +894,16 @@ static void sugov_limits(struct cpufreq_policy *policy) mutex_unlock(&sg_policy->work_lock); } - sg_policy->limits_changed = true; + /* + * The limits_changed update below must take place before the updates + * of policy limits in cpufreq_set_policy() or a policy limits update + * might be missed, so use a memory barrier to ensure it. + * + * This pairs with the memory barrier in sugov_should_update_freq(). + */ + smp_wmb(); + + WRITE_ONCE(sg_policy->limits_changed, true); } struct cpufreq_governor schedutil_gov = {

1 week, 4 days

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FAILED: patch "[PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x f1fb088d9cecde5c3066d8ff8846789667519b7d # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042806-rentable-announcer-3863@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From f1fb088d9cecde5c3066d8ff8846789667519b7d Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Fri, 4 Apr 2025 12:38:19 -0700 Subject: [PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass producer Take irqfds.lock when adding/deleting an IRQ bypass producer to ensure irqfd->producer isn't modified while kvm_irq_routing_update() is running. The only lock held when a producer is added/removed is irqbypass's mutex. Fixes: 872768800652 ("KVM: x86: select IRQ_BYPASS_MANAGER") Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-ID: <20250404193923.1413163-5-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 9c98b77b7dc1..a6829a370e6a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13561,15 +13561,22 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; int ret; - irqfd->producer = prod; kvm_arch_start_assignment(irqfd->kvm); + + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = prod; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 1); if (ret) kvm_arch_end_assignment(irqfd->kvm); + spin_unlock_irq(&kvm->irqfds.lock); + + return ret; } @@ -13579,9 +13586,9 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, int ret; struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; WARN_ON(irqfd->producer != prod); - irqfd->producer = NULL; /* * When producer of consumer is unregistered, we change back to @@ -13589,12 +13596,18 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, * when the irq is masked/disabled or the consumer side (KVM * int this case doesn't want to receive the interrupts. */ + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = NULL; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 0); if (ret) printk(KERN_INFO "irq bypass consumer (token %p) unregistration" " fails: %d\n", irqfd->consumer.token, ret); + spin_unlock_irq(&kvm->irqfds.lock); + + kvm_arch_end_assignment(irqfd->kvm); }

1 week, 4 days

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FAILED: patch "[PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass" failed to apply to 5.10-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x f1fb088d9cecde5c3066d8ff8846789667519b7d # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042806-economic-dexterous-1dcd@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From f1fb088d9cecde5c3066d8ff8846789667519b7d Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Fri, 4 Apr 2025 12:38:19 -0700 Subject: [PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass producer Take irqfds.lock when adding/deleting an IRQ bypass producer to ensure irqfd->producer isn't modified while kvm_irq_routing_update() is running. The only lock held when a producer is added/removed is irqbypass's mutex. Fixes: 872768800652 ("KVM: x86: select IRQ_BYPASS_MANAGER") Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-ID: <20250404193923.1413163-5-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 9c98b77b7dc1..a6829a370e6a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13561,15 +13561,22 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; int ret; - irqfd->producer = prod; kvm_arch_start_assignment(irqfd->kvm); + + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = prod; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 1); if (ret) kvm_arch_end_assignment(irqfd->kvm); + spin_unlock_irq(&kvm->irqfds.lock); + + return ret; } @@ -13579,9 +13586,9 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, int ret; struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; WARN_ON(irqfd->producer != prod); - irqfd->producer = NULL; /* * When producer of consumer is unregistered, we change back to @@ -13589,12 +13596,18 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, * when the irq is masked/disabled or the consumer side (KVM * int this case doesn't want to receive the interrupts. */ + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = NULL; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 0); if (ret) printk(KERN_INFO "irq bypass consumer (token %p) unregistration" " fails: %d\n", irqfd->consumer.token, ret); + spin_unlock_irq(&kvm->irqfds.lock); + + kvm_arch_end_assignment(irqfd->kvm); }

1 week, 4 days

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FAILED: patch "[PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x f1fb088d9cecde5c3066d8ff8846789667519b7d # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042806-shrubs-shining-b8f4@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From f1fb088d9cecde5c3066d8ff8846789667519b7d Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Fri, 4 Apr 2025 12:38:19 -0700 Subject: [PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass producer Take irqfds.lock when adding/deleting an IRQ bypass producer to ensure irqfd->producer isn't modified while kvm_irq_routing_update() is running. The only lock held when a producer is added/removed is irqbypass's mutex. Fixes: 872768800652 ("KVM: x86: select IRQ_BYPASS_MANAGER") Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-ID: <20250404193923.1413163-5-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 9c98b77b7dc1..a6829a370e6a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13561,15 +13561,22 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; int ret; - irqfd->producer = prod; kvm_arch_start_assignment(irqfd->kvm); + + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = prod; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 1); if (ret) kvm_arch_end_assignment(irqfd->kvm); + spin_unlock_irq(&kvm->irqfds.lock); + + return ret; } @@ -13579,9 +13586,9 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, int ret; struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; WARN_ON(irqfd->producer != prod); - irqfd->producer = NULL; /* * When producer of consumer is unregistered, we change back to @@ -13589,12 +13596,18 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, * when the irq is masked/disabled or the consumer side (KVM * int this case doesn't want to receive the interrupts. */ + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = NULL; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 0); if (ret) printk(KERN_INFO "irq bypass consumer (token %p) unregistration" " fails: %d\n", irqfd->consumer.token, ret); + spin_unlock_irq(&kvm->irqfds.lock); + + kvm_arch_end_assignment(irqfd->kvm); }

1 week, 5 days

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FAILED: patch "[PATCH] memcg: drain obj stock on cpu hotplug teardown" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025032807-famished-reprocess-abd3@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb Mon Sep 17 00:00:00 2001 From: Shakeel Butt <shakeel.butt(a)linux.dev> Date: Mon, 10 Mar 2025 16:09:34 -0700 Subject: [PATCH] memcg: drain obj stock on cpu hotplug teardown Currently on cpu hotplug teardown, only memcg stock is drained but we need to drain the obj stock as well otherwise we will miss the stats accumulated on the target cpu as well as the nr_bytes cached. The stats include MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B. In addition we are leaking reference to struct obj_cgroup object. Link: https://lkml.kernel.org/r/20250310230934.2913113-1-shakeel.butt@linux.dev Fixes: bf4f059954dc ("mm: memcg/slab: obj_cgroup API") Signed-off-by: Shakeel Butt <shakeel.butt(a)linux.dev> Reviewed-by: Roman Gushchin <roman.gushchin(a)linux.dev> Acked-by: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Muchun Song <muchun.song(a)linux.dev> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 8f9b35f80e24..a037ec92881d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1921,9 +1921,18 @@ void drain_all_stock(struct mem_cgroup *root_memcg) static int memcg_hotplug_cpu_dead(unsigned int cpu) { struct memcg_stock_pcp *stock; + struct obj_cgroup *old; + unsigned long flags; stock = &per_cpu(memcg_stock, cpu); + + /* drain_obj_stock requires stock_lock */ + local_lock_irqsave(&memcg_stock.stock_lock, flags); + old = drain_obj_stock(stock); + local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + drain_stock(stock); + obj_cgroup_put(old); return 0; }

1 week, 5 days

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FAILED: patch "[PATCH] memcg: drain obj stock on cpu hotplug teardown" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025050155-approve-flatly-068d@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb Mon Sep 17 00:00:00 2001 From: Shakeel Butt <shakeel.butt(a)linux.dev> Date: Mon, 10 Mar 2025 16:09:34 -0700 Subject: [PATCH] memcg: drain obj stock on cpu hotplug teardown Currently on cpu hotplug teardown, only memcg stock is drained but we need to drain the obj stock as well otherwise we will miss the stats accumulated on the target cpu as well as the nr_bytes cached. The stats include MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B. In addition we are leaking reference to struct obj_cgroup object. Link: https://lkml.kernel.org/r/20250310230934.2913113-1-shakeel.butt@linux.dev Fixes: bf4f059954dc ("mm: memcg/slab: obj_cgroup API") Signed-off-by: Shakeel Butt <shakeel.butt(a)linux.dev> Reviewed-by: Roman Gushchin <roman.gushchin(a)linux.dev> Acked-by: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Muchun Song <muchun.song(a)linux.dev> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 8f9b35f80e24..a037ec92881d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1921,9 +1921,18 @@ void drain_all_stock(struct mem_cgroup *root_memcg) static int memcg_hotplug_cpu_dead(unsigned int cpu) { struct memcg_stock_pcp *stock; + struct obj_cgroup *old; + unsigned long flags; stock = &per_cpu(memcg_stock, cpu); + + /* drain_obj_stock requires stock_lock */ + local_lock_irqsave(&memcg_stock.stock_lock, flags); + old = drain_obj_stock(stock); + local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + drain_stock(stock); + obj_cgroup_put(old); return 0; }

1 week, 5 days

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FAILED: patch "[PATCH] memcg: drain obj stock on cpu hotplug teardown" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025032853-copy-crank-1c82@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb Mon Sep 17 00:00:00 2001 From: Shakeel Butt <shakeel.butt(a)linux.dev> Date: Mon, 10 Mar 2025 16:09:34 -0700 Subject: [PATCH] memcg: drain obj stock on cpu hotplug teardown Currently on cpu hotplug teardown, only memcg stock is drained but we need to drain the obj stock as well otherwise we will miss the stats accumulated on the target cpu as well as the nr_bytes cached. The stats include MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B. In addition we are leaking reference to struct obj_cgroup object. Link: https://lkml.kernel.org/r/20250310230934.2913113-1-shakeel.butt@linux.dev Fixes: bf4f059954dc ("mm: memcg/slab: obj_cgroup API") Signed-off-by: Shakeel Butt <shakeel.butt(a)linux.dev> Reviewed-by: Roman Gushchin <roman.gushchin(a)linux.dev> Acked-by: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Muchun Song <muchun.song(a)linux.dev> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 8f9b35f80e24..a037ec92881d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1921,9 +1921,18 @@ void drain_all_stock(struct mem_cgroup *root_memcg) static int memcg_hotplug_cpu_dead(unsigned int cpu) { struct memcg_stock_pcp *stock; + struct obj_cgroup *old; + unsigned long flags; stock = &per_cpu(memcg_stock, cpu); + + /* drain_obj_stock requires stock_lock */ + local_lock_irqsave(&memcg_stock.stock_lock, flags); + old = drain_obj_stock(stock); + local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + drain_stock(stock); + obj_cgroup_put(old); return 0; }

1 week, 5 days

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FAILED: patch "[PATCH] btrfs: adjust subpage bit start based on sectorsize" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x e08e49d986f82c30f42ad0ed43ebbede1e1e3739 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025050516-festivity-author-89a7@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e08e49d986f82c30f42ad0ed43ebbede1e1e3739 Mon Sep 17 00:00:00 2001 From: Josef Bacik <josef(a)toxicpanda.com> Date: Mon, 14 Apr 2025 14:51:58 -0400 Subject: [PATCH] btrfs: adjust subpage bit start based on sectorsize When running machines with 64k page size and a 16k nodesize we started seeing tree log corruption in production. This turned out to be because we were not writing out dirty blocks sometimes, so this in fact affects all metadata writes. When writing out a subpage EB we scan the subpage bitmap for a dirty range. If the range isn't dirty we do bit_start++; to move onto the next bit. The problem is the bitmap is based on the number of sectors that an EB has. So in this case, we have a 64k pagesize, 16k nodesize, but a 4k sectorsize. This means our bitmap is 4 bits for every node. With a 64k page size we end up with 4 nodes per page. To make this easier this is how everything looks [0 16k 32k 48k ] logical address [0 4 8 12 ] radix tree offset [ 64k page ] folio [ 16k eb ][ 16k eb ][ 16k eb ][ 16k eb ] extent buffers [ | | | | | | | | | | | | | | | | ] bitmap Now we use all of our addressing based on fs_info->sectorsize_bits, so as you can see the above our 16k eb->start turns into radix entry 4. When we find a dirty range for our eb, we correctly do bit_start += sectors_per_node, because if we start at bit 0, the next bit for the next eb is 4, to correspond to eb->start 16k. However if our range is clean, we will do bit_start++, which will now put us offset from our radix tree entries. In our case, assume that the first time we check the bitmap the block is not dirty, we increment bit_start so now it == 1, and then we loop around and check again. This time it is dirty, and we go to find that start using the following equation start = folio_start + bit_start * fs_info->sectorsize; so in the case above, eb->start 0 is now dirty, and we calculate start as 0 + 1 * fs_info->sectorsize = 4096 4096 >> 12 = 1 Now we're looking up the radix tree for 1, and we won't find an eb. What's worse is now we're using bit_start == 1, so we do bit_start += sectors_per_node, which is now 5. If that eb is dirty we will run into the same thing, we will look at an offset that is not populated in the radix tree, and now we're skipping the writeout of dirty extent buffers. The best fix for this is to not use sectorsize_bits to address nodes, but that's a larger change. Since this is a fs corruption problem fix it simply by always using sectors_per_node to increment the start bit. Fixes: c4aec299fa8f ("btrfs: introduce submit_eb_subpage() to submit a subpage metadata page") CC: stable(a)vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov <boris(a)bur.io> Reviewed-by: Qu Wenruo <wqu(a)suse.com> Signed-off-by: Josef Bacik <josef(a)toxicpanda.com> Signed-off-by: David Sterba <dsterba(a)suse.com> diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 197f5e51c474..8515c31f563b 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2047,7 +2047,7 @@ static int submit_eb_subpage(struct folio *folio, struct writeback_control *wbc) subpage->bitmaps)) { spin_unlock_irqrestore(&subpage->lock, flags); spin_unlock(&folio->mapping->i_private_lock); - bit_start++; + bit_start += sectors_per_node; continue; }

1 week, 5 days

2
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FAILED: patch "[PATCH] memcg: drain obj stock on cpu hotplug teardown" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025050154-cubical-audience-b6a2@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 9f01b4954490d4ccdbcc2b9be34a9921ceee9cbb Mon Sep 17 00:00:00 2001 From: Shakeel Butt <shakeel.butt(a)linux.dev> Date: Mon, 10 Mar 2025 16:09:34 -0700 Subject: [PATCH] memcg: drain obj stock on cpu hotplug teardown Currently on cpu hotplug teardown, only memcg stock is drained but we need to drain the obj stock as well otherwise we will miss the stats accumulated on the target cpu as well as the nr_bytes cached. The stats include MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B. In addition we are leaking reference to struct obj_cgroup object. Link: https://lkml.kernel.org/r/20250310230934.2913113-1-shakeel.butt@linux.dev Fixes: bf4f059954dc ("mm: memcg/slab: obj_cgroup API") Signed-off-by: Shakeel Butt <shakeel.butt(a)linux.dev> Reviewed-by: Roman Gushchin <roman.gushchin(a)linux.dev> Acked-by: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Muchun Song <muchun.song(a)linux.dev> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 8f9b35f80e24..a037ec92881d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1921,9 +1921,18 @@ void drain_all_stock(struct mem_cgroup *root_memcg) static int memcg_hotplug_cpu_dead(unsigned int cpu) { struct memcg_stock_pcp *stock; + struct obj_cgroup *old; + unsigned long flags; stock = &per_cpu(memcg_stock, cpu); + + /* drain_obj_stock requires stock_lock */ + local_lock_irqsave(&memcg_stock.stock_lock, flags); + old = drain_obj_stock(stock); + local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + drain_stock(stock); + obj_cgroup_put(old); return 0; }

1 week, 5 days

2
1
0 0

FAILED: patch "[PATCH] btrfs: adjust subpage bit start based on sectorsize" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x e08e49d986f82c30f42ad0ed43ebbede1e1e3739 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025050512-showpiece-rehab-9f57@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e08e49d986f82c30f42ad0ed43ebbede1e1e3739 Mon Sep 17 00:00:00 2001 From: Josef Bacik <josef(a)toxicpanda.com> Date: Mon, 14 Apr 2025 14:51:58 -0400 Subject: [PATCH] btrfs: adjust subpage bit start based on sectorsize When running machines with 64k page size and a 16k nodesize we started seeing tree log corruption in production. This turned out to be because we were not writing out dirty blocks sometimes, so this in fact affects all metadata writes. When writing out a subpage EB we scan the subpage bitmap for a dirty range. If the range isn't dirty we do bit_start++; to move onto the next bit. The problem is the bitmap is based on the number of sectors that an EB has. So in this case, we have a 64k pagesize, 16k nodesize, but a 4k sectorsize. This means our bitmap is 4 bits for every node. With a 64k page size we end up with 4 nodes per page. To make this easier this is how everything looks [0 16k 32k 48k ] logical address [0 4 8 12 ] radix tree offset [ 64k page ] folio [ 16k eb ][ 16k eb ][ 16k eb ][ 16k eb ] extent buffers [ | | | | | | | | | | | | | | | | ] bitmap Now we use all of our addressing based on fs_info->sectorsize_bits, so as you can see the above our 16k eb->start turns into radix entry 4. When we find a dirty range for our eb, we correctly do bit_start += sectors_per_node, because if we start at bit 0, the next bit for the next eb is 4, to correspond to eb->start 16k. However if our range is clean, we will do bit_start++, which will now put us offset from our radix tree entries. In our case, assume that the first time we check the bitmap the block is not dirty, we increment bit_start so now it == 1, and then we loop around and check again. This time it is dirty, and we go to find that start using the following equation start = folio_start + bit_start * fs_info->sectorsize; so in the case above, eb->start 0 is now dirty, and we calculate start as 0 + 1 * fs_info->sectorsize = 4096 4096 >> 12 = 1 Now we're looking up the radix tree for 1, and we won't find an eb. What's worse is now we're using bit_start == 1, so we do bit_start += sectors_per_node, which is now 5. If that eb is dirty we will run into the same thing, we will look at an offset that is not populated in the radix tree, and now we're skipping the writeout of dirty extent buffers. The best fix for this is to not use sectorsize_bits to address nodes, but that's a larger change. Since this is a fs corruption problem fix it simply by always using sectors_per_node to increment the start bit. Fixes: c4aec299fa8f ("btrfs: introduce submit_eb_subpage() to submit a subpage metadata page") CC: stable(a)vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov <boris(a)bur.io> Reviewed-by: Qu Wenruo <wqu(a)suse.com> Signed-off-by: Josef Bacik <josef(a)toxicpanda.com> Signed-off-by: David Sterba <dsterba(a)suse.com> diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 197f5e51c474..8515c31f563b 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2047,7 +2047,7 @@ static int submit_eb_subpage(struct folio *folio, struct writeback_control *wbc) subpage->bitmaps)) { spin_unlock_irqrestore(&subpage->lock, flags); spin_unlock(&folio->mapping->i_private_lock); - bit_start++; + bit_start += sectors_per_node; continue; }

1 week, 5 days

2
1
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