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 23b53639a793477326fd57ed103823a8ab63084f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101641-palpitate-pesticide-3ad4@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 23b53639a793477326fd57ed103823a8ab63084f Mon Sep 17 00:00:00 2001
From: Thomas Fourier <fourier.thomas(a)gmail.com>
Date: Wed, 9 Jul 2025 13:35:40 +0200
Subject: [PATCH] media: cx18: Add missing check after DMA map
The DMA map functions can fail and should be tested for errors.
If the mapping fails, dealloc buffers, and return.
Fixes: 1c1e45d17b66 ("V4L/DVB (7786): cx18: new driver for the Conexant CX23418 MPEG encoder chip")
Cc: stable(a)vger.kernel.org
Signed-off-by: Thomas Fourier <fourier.thomas(a)gmail.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco(a)kernel.org>
diff --git a/drivers/media/pci/cx18/cx18-queue.c b/drivers/media/pci/cx18/cx18-queue.c
index 013694bfcb1c..7cbb2d586932 100644
--- a/drivers/media/pci/cx18/cx18-queue.c
+++ b/drivers/media/pci/cx18/cx18-queue.c
@@ -379,15 +379,22 @@ int cx18_stream_alloc(struct cx18_stream *s)
break;
}
+ buf->dma_handle = dma_map_single(&s->cx->pci_dev->dev,
+ buf->buf, s->buf_size,
+ s->dma);
+ if (dma_mapping_error(&s->cx->pci_dev->dev, buf->dma_handle)) {
+ kfree(buf->buf);
+ kfree(mdl);
+ kfree(buf);
+ break;
+ }
+
INIT_LIST_HEAD(&mdl->list);
INIT_LIST_HEAD(&mdl->buf_list);
mdl->id = s->mdl_base_idx; /* a somewhat safe value */
cx18_enqueue(s, mdl, &s->q_idle);
INIT_LIST_HEAD(&buf->list);
- buf->dma_handle = dma_map_single(&s->cx->pci_dev->dev,
- buf->buf, s->buf_size,
- s->dma);
cx18_buf_sync_for_cpu(s, buf);
list_add_tail(&buf->list, &s->buf_pool);
}
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 3fcc8e146935415d69ffabb5df40ecf50e106131
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101617-tadpole-sneer-4143@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3fcc8e146935415d69ffabb5df40ecf50e106131 Mon Sep 17 00:00:00 2001
From: Jason Andryuk <jason.andryuk(a)amd.com>
Date: Wed, 27 Aug 2025 20:36:03 -0400
Subject: [PATCH] xen/events: Update virq_to_irq on migration
VIRQs come in 3 flavors, per-VPU, per-domain, and global, and the VIRQs
are tracked in per-cpu virq_to_irq arrays.
Per-domain and global VIRQs must be bound on CPU 0, and
bind_virq_to_irq() sets the per_cpu virq_to_irq at registration time
Later, the interrupt can migrate, and info->cpu is updated. When
calling __unbind_from_irq(), the per-cpu virq_to_irq is cleared for a
different cpu. If bind_virq_to_irq() is called again with CPU 0, the
stale irq is returned. There won't be any irq_info for the irq, so
things break.
Make xen_rebind_evtchn_to_cpu() update the per_cpu virq_to_irq mappings
to keep them update to date with the current cpu. This ensures the
correct virq_to_irq is cleared in __unbind_from_irq().
Fixes: e46cdb66c8fc ("xen: event channels")
Cc: stable(a)vger.kernel.org
Signed-off-by: Jason Andryuk <jason.andryuk(a)amd.com>
Reviewed-by: Juergen Gross <jgross(a)suse.com>
Signed-off-by: Juergen Gross <jgross(a)suse.com>
Message-ID: <20250828003604.8949-4-jason.andryuk(a)amd.com>
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index b060b5a95f45..9478fae014e5 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -1797,9 +1797,20 @@ static int xen_rebind_evtchn_to_cpu(struct irq_info *info, unsigned int tcpu)
* virq or IPI channel, which don't actually need to be rebound. Ignore
* it, but don't do the xenlinux-level rebind in that case.
*/
- if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0) {
+ int old_cpu = info->cpu;
+
bind_evtchn_to_cpu(info, tcpu, false);
+ if (info->type == IRQT_VIRQ) {
+ int virq = info->u.virq;
+ int irq = per_cpu(virq_to_irq, old_cpu)[virq];
+
+ per_cpu(virq_to_irq, old_cpu)[virq] = -1;
+ per_cpu(virq_to_irq, tcpu)[virq] = irq;
+ }
+ }
+
do_unmask(info, EVT_MASK_REASON_TEMPORARY);
return 0;
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 23b53639a793477326fd57ed103823a8ab63084f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101641-imminent-rentable-bc13@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 23b53639a793477326fd57ed103823a8ab63084f Mon Sep 17 00:00:00 2001
From: Thomas Fourier <fourier.thomas(a)gmail.com>
Date: Wed, 9 Jul 2025 13:35:40 +0200
Subject: [PATCH] media: cx18: Add missing check after DMA map
The DMA map functions can fail and should be tested for errors.
If the mapping fails, dealloc buffers, and return.
Fixes: 1c1e45d17b66 ("V4L/DVB (7786): cx18: new driver for the Conexant CX23418 MPEG encoder chip")
Cc: stable(a)vger.kernel.org
Signed-off-by: Thomas Fourier <fourier.thomas(a)gmail.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco(a)kernel.org>
diff --git a/drivers/media/pci/cx18/cx18-queue.c b/drivers/media/pci/cx18/cx18-queue.c
index 013694bfcb1c..7cbb2d586932 100644
--- a/drivers/media/pci/cx18/cx18-queue.c
+++ b/drivers/media/pci/cx18/cx18-queue.c
@@ -379,15 +379,22 @@ int cx18_stream_alloc(struct cx18_stream *s)
break;
}
+ buf->dma_handle = dma_map_single(&s->cx->pci_dev->dev,
+ buf->buf, s->buf_size,
+ s->dma);
+ if (dma_mapping_error(&s->cx->pci_dev->dev, buf->dma_handle)) {
+ kfree(buf->buf);
+ kfree(mdl);
+ kfree(buf);
+ break;
+ }
+
INIT_LIST_HEAD(&mdl->list);
INIT_LIST_HEAD(&mdl->buf_list);
mdl->id = s->mdl_base_idx; /* a somewhat safe value */
cx18_enqueue(s, mdl, &s->q_idle);
INIT_LIST_HEAD(&buf->list);
- buf->dma_handle = dma_map_single(&s->cx->pci_dev->dev,
- buf->buf, s->buf_size,
- s->dma);
cx18_buf_sync_for_cpu(s, buf);
list_add_tail(&buf->list, &s->buf_pool);
}
Hi Greg,
On 16/10/2025 15:25, gregkh(a)linuxfoundation.org wrote:
>
> This is a note to let you know that I've just added the patch titled
>
> selftests: mptcp: join: validate C-flag + def limit
>
> to the 5.15-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
>
> The filename of the patch is:
> selftests-mptcp-join-validate-c-flag-def-limit.patch
> and it can be found in the queue-5.15 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable(a)vger.kernel.org> know about it.
It looks like this patch was applied at the wrong place, and further
adaptations are needed to work in v5.15. Do you mind dropping it from
the v5.15 tree, please?
I will send a newer version later on.
Cheers,
Matt
--
Sponsored by the NGI0 Core fund.
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 f620d66af3165838bfa845dcf9f5f9b4089bf508
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101648-stimulate-stallion-5b49@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f620d66af3165838bfa845dcf9f5f9b4089bf508 Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas(a)arm.com>
Date: Wed, 24 Sep 2025 13:31:22 +0100
Subject: [PATCH] arm64: mte: Do not flag the zero page as PG_mte_tagged
Commit 68d54ceeec0e ("arm64: mte: Allow PTRACE_PEEKMTETAGS access to the
zero page") attempted to fix ptrace() reading of tags from the zero page
by marking it as PG_mte_tagged during cpu_enable_mte(). The same commit
also changed the ptrace() tag access permission check to the VM_MTE vma
flag while turning the page flag test into a WARN_ON_ONCE().
Attempting to set the PG_mte_tagged flag early with
CONFIG_DEFERRED_STRUCT_PAGE_INIT enabled may either hang (after commit
d77e59a8fccd "arm64: mte: Lock a page for MTE tag initialisation") or
have the flags cleared later during page_alloc_init_late(). In addition,
pages_identical() -> memcmp_pages() will reject any comparison with the
zero page as it is marked as tagged.
Partially revert the above commit to avoid setting PG_mte_tagged on the
zero page. Update the __access_remote_tags() warning on untagged pages
to ignore the zero page since it is known to have the tags initialised.
Note that all user mapping of the zero page are marked as pte_special().
The arm64 set_pte_at() will not call mte_sync_tags() on such pages, so
PG_mte_tagged will remain cleared.
Signed-off-by: Catalin Marinas <catalin.marinas(a)arm.com>
Fixes: 68d54ceeec0e ("arm64: mte: Allow PTRACE_PEEKMTETAGS access to the zero page")
Reported-by: Gergely Kovacs <Gergely.Kovacs2(a)arm.com>
Cc: stable(a)vger.kernel.org # 5.10.x
Cc: Will Deacon <will(a)kernel.org>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Lance Yang <lance.yang(a)linux.dev>
Acked-by: Lance Yang <lance.yang(a)linux.dev>
Reviewed-by: David Hildenbrand <david(a)redhat.com>
Tested-by: Lance Yang <lance.yang(a)linux.dev>
Signed-off-by: Will Deacon <will(a)kernel.org>
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index ecb83ab0700e..7345987a50a0 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2303,17 +2303,21 @@ static void bti_enable(const struct arm64_cpu_capabilities *__unused)
#ifdef CONFIG_ARM64_MTE
static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
{
+ static bool cleared_zero_page = false;
+
sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_ATA | SCTLR_EL1_ATA0);
mte_cpu_setup();
/*
* Clear the tags in the zero page. This needs to be done via the
- * linear map which has the Tagged attribute.
+ * linear map which has the Tagged attribute. Since this page is
+ * always mapped as pte_special(), set_pte_at() will not attempt to
+ * clear the tags or set PG_mte_tagged.
*/
- if (try_page_mte_tagging(ZERO_PAGE(0))) {
+ if (!cleared_zero_page) {
+ cleared_zero_page = true;
mte_clear_page_tags(lm_alias(empty_zero_page));
- set_page_mte_tagged(ZERO_PAGE(0));
}
kasan_init_hw_tags_cpu();
diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c
index e5e773844889..63aed49ac181 100644
--- a/arch/arm64/kernel/mte.c
+++ b/arch/arm64/kernel/mte.c
@@ -460,7 +460,7 @@ static int __access_remote_tags(struct mm_struct *mm, unsigned long addr,
if (folio_test_hugetlb(folio))
WARN_ON_ONCE(!folio_test_hugetlb_mte_tagged(folio));
else
- WARN_ON_ONCE(!page_mte_tagged(page));
+ WARN_ON_ONCE(!page_mte_tagged(page) && !is_zero_page(page));
/* limit access to the end of the page */
offset = offset_in_page(addr);
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 23b53639a793477326fd57ed103823a8ab63084f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101641-clutter-scruffy-a000@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 23b53639a793477326fd57ed103823a8ab63084f Mon Sep 17 00:00:00 2001
From: Thomas Fourier <fourier.thomas(a)gmail.com>
Date: Wed, 9 Jul 2025 13:35:40 +0200
Subject: [PATCH] media: cx18: Add missing check after DMA map
The DMA map functions can fail and should be tested for errors.
If the mapping fails, dealloc buffers, and return.
Fixes: 1c1e45d17b66 ("V4L/DVB (7786): cx18: new driver for the Conexant CX23418 MPEG encoder chip")
Cc: stable(a)vger.kernel.org
Signed-off-by: Thomas Fourier <fourier.thomas(a)gmail.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco(a)kernel.org>
diff --git a/drivers/media/pci/cx18/cx18-queue.c b/drivers/media/pci/cx18/cx18-queue.c
index 013694bfcb1c..7cbb2d586932 100644
--- a/drivers/media/pci/cx18/cx18-queue.c
+++ b/drivers/media/pci/cx18/cx18-queue.c
@@ -379,15 +379,22 @@ int cx18_stream_alloc(struct cx18_stream *s)
break;
}
+ buf->dma_handle = dma_map_single(&s->cx->pci_dev->dev,
+ buf->buf, s->buf_size,
+ s->dma);
+ if (dma_mapping_error(&s->cx->pci_dev->dev, buf->dma_handle)) {
+ kfree(buf->buf);
+ kfree(mdl);
+ kfree(buf);
+ break;
+ }
+
INIT_LIST_HEAD(&mdl->list);
INIT_LIST_HEAD(&mdl->buf_list);
mdl->id = s->mdl_base_idx; /* a somewhat safe value */
cx18_enqueue(s, mdl, &s->q_idle);
INIT_LIST_HEAD(&buf->list);
- buf->dma_handle = dma_map_single(&s->cx->pci_dev->dev,
- buf->buf, s->buf_size,
- s->dma);
cx18_buf_sync_for_cpu(s, buf);
list_add_tail(&buf->list, &s->buf_pool);
}
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 08df2d7dd4ab2db8a172d824cda7872d5eca460a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101626-colony-unbend-f00e@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 08df2d7dd4ab2db8a172d824cda7872d5eca460a Mon Sep 17 00:00:00 2001
From: Jason Andryuk <jason.andryuk(a)amd.com>
Date: Wed, 27 Aug 2025 20:36:01 -0400
Subject: [PATCH] xen/events: Cleanup find_virq() return codes
rc is overwritten by the evtchn_status hypercall in each iteration, so
the return value will be whatever the last iteration is. This could
incorrectly return success even if the event channel was not found.
Change to an explicit -ENOENT for an un-found virq and return 0 on a
successful match.
Fixes: 62cc5fc7b2e0 ("xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports")
Cc: stable(a)vger.kernel.org
Signed-off-by: Jason Andryuk <jason.andryuk(a)amd.com>
Reviewed-by: Jan Beulich <jbeulich(a)suse.com>
Reviewed-by: Juergen Gross <jgross(a)suse.com>
Signed-off-by: Juergen Gross <jgross(a)suse.com>
Message-ID: <20250828003604.8949-2-jason.andryuk(a)amd.com>
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 41309d38f78c..374231d84e4f 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -1318,10 +1318,11 @@ static int find_virq(unsigned int virq, unsigned int cpu, evtchn_port_t *evtchn)
{
struct evtchn_status status;
evtchn_port_t port;
- int rc = -ENOENT;
memset(&status, 0, sizeof(status));
for (port = 0; port < xen_evtchn_max_channels(); port++) {
+ int rc;
+
status.dom = DOMID_SELF;
status.port = port;
rc = HYPERVISOR_event_channel_op(EVTCHNOP_status, &status);
@@ -1331,10 +1332,10 @@ static int find_virq(unsigned int virq, unsigned int cpu, evtchn_port_t *evtchn)
continue;
if (status.u.virq == virq && status.vcpu == xen_vcpu_nr(cpu)) {
*evtchn = port;
- break;
+ return 0;
}
}
- return rc;
+ return -ENOENT;
}
/**
rtla-timerlat allows a *thread* latency threshold to be set via the
-T/--thread option. However, the timerlat tracer calls this *total*
latency (stop_tracing_total_us), and stops tracing also when the
return-to-user latency is over the threshold.
Change the behavior of the timerlat BPF program to reflect what the
timerlat tracer is doing, to avoid discrepancy between stopping
collecting data in the BPF program and stopping tracing in the timerlat
tracer.
Cc: stable(a)vger.kernel.org
Fixes: e34293ddcebd ("rtla/timerlat: Add BPF skeleton to collect samples")
Signed-off-by: Tomas Glozar <tglozar(a)redhat.com>
---
tools/tracing/rtla/src/timerlat.bpf.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/tracing/rtla/src/timerlat.bpf.c b/tools/tracing/rtla/src/timerlat.bpf.c
index 084cd10c21fc..e2265b5d6491 100644
--- a/tools/tracing/rtla/src/timerlat.bpf.c
+++ b/tools/tracing/rtla/src/timerlat.bpf.c
@@ -148,6 +148,9 @@ int handle_timerlat_sample(struct trace_event_raw_timerlat_sample *tp_args)
} else {
update_main_hist(&hist_user, bucket);
update_summary(&summary_user, latency, bucket);
+
+ if (thread_threshold != 0 && latency_us >= thread_threshold)
+ set_stop_tracing();
}
return 0;
--
2.51.0
The patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 9658d698a8a83540bf6a6c80d13c9a61590ee985
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101627-shortage-author-7f5b@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 9658d698a8a83540bf6a6c80d13c9a61590ee985 Mon Sep 17 00:00:00 2001
From: Lance Yang <lance.yang(a)linux.dev>
Date: Tue, 30 Sep 2025 16:10:40 +0800
Subject: [PATCH] mm/rmap: fix soft-dirty and uffd-wp bit loss when remapping
zero-filled mTHP subpage to shared zeropage
When splitting an mTHP and replacing a zero-filled subpage with the shared
zeropage, try_to_map_unused_to_zeropage() currently drops several
important PTE bits.
For userspace tools like CRIU, which rely on the soft-dirty mechanism for
incremental snapshots, losing the soft-dirty bit means modified pages are
missed, leading to inconsistent memory state after restore.
As pointed out by David, the more critical uffd-wp bit is also dropped.
This breaks the userfaultfd write-protection mechanism, causing writes to
be silently missed by monitoring applications, which can lead to data
corruption.
Preserve both the soft-dirty and uffd-wp bits from the old PTE when
creating the new zeropage mapping to ensure they are correctly tracked.
Link: https://lkml.kernel.org/r/20250930081040.80926-1-lance.yang@linux.dev
Fixes: b1f202060afe ("mm: remap unused subpages to shared zeropage when splitting isolated thp")
Signed-off-by: Lance Yang <lance.yang(a)linux.dev>
Suggested-by: David Hildenbrand <david(a)redhat.com>
Suggested-by: Dev Jain <dev.jain(a)arm.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Reviewed-by: Dev Jain <dev.jain(a)arm.com>
Acked-by: Zi Yan <ziy(a)nvidia.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Reviewed-by: Harry Yoo <harry.yoo(a)oracle.com>
Cc: Alistair Popple <apopple(a)nvidia.com>
Cc: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Cc: Barry Song <baohua(a)kernel.org>
Cc: Byungchul Park <byungchul(a)sk.com>
Cc: Gregory Price <gourry(a)gourry.net>
Cc: "Huang, Ying" <ying.huang(a)linux.alibaba.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Joshua Hahn <joshua.hahnjy(a)gmail.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Mariano Pache <npache(a)redhat.com>
Cc: Mathew Brost <matthew.brost(a)intel.com>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Rakie Kim <rakie.kim(a)sk.com>
Cc: Rik van Riel <riel(a)surriel.com>
Cc: Ryan Roberts <ryan.roberts(a)arm.com>
Cc: Usama Arif <usamaarif642(a)gmail.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: Yu Zhao <yuzhao(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/migrate.c b/mm/migrate.c
index ce83c2c3c287..e3065c9edb55 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -296,8 +296,7 @@ bool isolate_folio_to_list(struct folio *folio, struct list_head *list)
}
static bool try_to_map_unused_to_zeropage(struct page_vma_mapped_walk *pvmw,
- struct folio *folio,
- unsigned long idx)
+ struct folio *folio, pte_t old_pte, unsigned long idx)
{
struct page *page = folio_page(folio, idx);
pte_t newpte;
@@ -306,7 +305,7 @@ static bool try_to_map_unused_to_zeropage(struct page_vma_mapped_walk *pvmw,
return false;
VM_BUG_ON_PAGE(!PageAnon(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
- VM_BUG_ON_PAGE(pte_present(ptep_get(pvmw->pte)), page);
+ VM_BUG_ON_PAGE(pte_present(old_pte), page);
if (folio_test_mlocked(folio) || (pvmw->vma->vm_flags & VM_LOCKED) ||
mm_forbids_zeropage(pvmw->vma->vm_mm))
@@ -322,6 +321,12 @@ static bool try_to_map_unused_to_zeropage(struct page_vma_mapped_walk *pvmw,
newpte = pte_mkspecial(pfn_pte(my_zero_pfn(pvmw->address),
pvmw->vma->vm_page_prot));
+
+ if (pte_swp_soft_dirty(old_pte))
+ newpte = pte_mksoft_dirty(newpte);
+ if (pte_swp_uffd_wp(old_pte))
+ newpte = pte_mkuffd_wp(newpte);
+
set_pte_at(pvmw->vma->vm_mm, pvmw->address, pvmw->pte, newpte);
dec_mm_counter(pvmw->vma->vm_mm, mm_counter(folio));
@@ -364,13 +369,13 @@ static bool remove_migration_pte(struct folio *folio,
continue;
}
#endif
+ old_pte = ptep_get(pvmw.pte);
if (rmap_walk_arg->map_unused_to_zeropage &&
- try_to_map_unused_to_zeropage(&pvmw, folio, idx))
+ try_to_map_unused_to_zeropage(&pvmw, folio, old_pte, idx))
continue;
folio_get(folio);
pte = mk_pte(new, READ_ONCE(vma->vm_page_prot));
- old_pte = ptep_get(pvmw.pte);
entry = pte_to_swp_entry(old_pte);
if (!is_migration_entry_young(entry))
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 4b1ff850e0c1aacc23e923ed22989b827b9808f9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101657-platform-jersey-adec@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4b1ff850e0c1aacc23e923ed22989b827b9808f9 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe(a)kernel.org>
Date: Thu, 25 Sep 2025 12:32:36 +0200
Subject: [PATCH] mptcp: pm: in-kernel: usable client side with C-flag
When servers set the C-flag in their MP_CAPABLE to tell clients not to
create subflows to the initial address and port, clients will likely not
use their other endpoints. That's because the in-kernel path-manager
uses the 'subflow' endpoints to create subflows only to the initial
address and port.
If the limits have not been modified to accept ADD_ADDR, the client
doesn't try to establish new subflows. If the limits accept ADD_ADDR,
the routing routes will be used to select the source IP.
The C-flag is typically set when the server is operating behind a legacy
Layer 4 load balancer, or using anycast IP address. Clients having their
different 'subflow' endpoints setup, don't end up creating multiple
subflows as expected, and causing some deployment issues.
A special case is then added here: when servers set the C-flag in the
MPC and directly sends an ADD_ADDR, this single ADD_ADDR is accepted.
The 'subflows' endpoints will then be used with this new remote IP and
port. This exception is only allowed when the ADD_ADDR is sent
immediately after the 3WHS, and makes the client switching to the 'fully
established' mode. After that, 'select_local_address()' will not be able
to find any subflows, because 'id_avail_bitmap' will be filled in
mptcp_pm_create_subflow_or_signal_addr(), when switching to 'fully
established' mode.
Fixes: df377be38725 ("mptcp: add deny_join_id0 in mptcp_options_received")
Cc: stable(a)vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/536
Reviewed-by: Geliang Tang <geliang(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20250925-net-next-mptcp-c-flag-laminar-v1-1-ad126c…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 204e1f61212e..584cab90aa6e 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -637,9 +637,12 @@ void mptcp_pm_add_addr_received(const struct sock *ssk,
} else {
__MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_ADDADDRDROP);
}
- /* id0 should not have a different address */
+ /* - id0 should not have a different address
+ * - special case for C-flag: linked to fill_local_addresses_vec()
+ */
} else if ((addr->id == 0 && !mptcp_pm_is_init_remote_addr(msk, addr)) ||
- (addr->id > 0 && !READ_ONCE(pm->accept_addr))) {
+ (addr->id > 0 && !READ_ONCE(pm->accept_addr) &&
+ !mptcp_pm_add_addr_c_flag_case(msk))) {
mptcp_pm_announce_addr(msk, addr, true);
mptcp_pm_add_addr_send_ack(msk);
} else if (mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED)) {
diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c
index 667803d72b64..8c46493a0835 100644
--- a/net/mptcp/pm_kernel.c
+++ b/net/mptcp/pm_kernel.c
@@ -389,10 +389,12 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
struct mptcp_addr_info mpc_addr;
struct pm_nl_pernet *pernet;
unsigned int subflows_max;
+ bool c_flag_case;
int i = 0;
pernet = pm_nl_get_pernet_from_msk(msk);
subflows_max = mptcp_pm_get_subflows_max(msk);
+ c_flag_case = remote->id && mptcp_pm_add_addr_c_flag_case(msk);
mptcp_local_address((struct sock_common *)msk, &mpc_addr);
@@ -405,12 +407,27 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
continue;
if (msk->pm.subflows < subflows_max) {
+ bool is_id0;
+
locals[i].addr = entry->addr;
locals[i].flags = entry->flags;
locals[i].ifindex = entry->ifindex;
+ is_id0 = mptcp_addresses_equal(&locals[i].addr,
+ &mpc_addr,
+ locals[i].addr.port);
+
+ if (c_flag_case &&
+ (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) {
+ __clear_bit(locals[i].addr.id,
+ msk->pm.id_avail_bitmap);
+
+ if (!is_id0)
+ msk->pm.local_addr_used++;
+ }
+
/* Special case for ID0: set the correct ID */
- if (mptcp_addresses_equal(&locals[i].addr, &mpc_addr, locals[i].addr.port))
+ if (is_id0)
locals[i].addr.id = 0;
msk->pm.subflows++;
@@ -419,6 +436,37 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
}
rcu_read_unlock();
+ /* Special case: peer sets the C flag, accept one ADD_ADDR if default
+ * limits are used -- accepting no ADD_ADDR -- and use subflow endpoints
+ */
+ if (!i && c_flag_case) {
+ unsigned int local_addr_max = mptcp_pm_get_local_addr_max(msk);
+
+ while (msk->pm.local_addr_used < local_addr_max &&
+ msk->pm.subflows < subflows_max) {
+ struct mptcp_pm_local *local = &locals[i];
+
+ if (!select_local_address(pernet, msk, local))
+ break;
+
+ __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
+
+ if (!mptcp_pm_addr_families_match(sk, &local->addr,
+ remote))
+ continue;
+
+ if (mptcp_addresses_equal(&local->addr, &mpc_addr,
+ local->addr.port))
+ continue;
+
+ msk->pm.local_addr_used++;
+ msk->pm.subflows++;
+ i++;
+ }
+
+ return i;
+ }
+
/* If the array is empty, fill in the single
* 'IPADDRANY' local address
*/
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index a1787a1344ac..cbe54331e5c7 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -1199,6 +1199,14 @@ static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk)
spin_unlock_bh(&msk->pm.lock);
}
+static inline bool mptcp_pm_add_addr_c_flag_case(struct mptcp_sock *msk)
+{
+ return READ_ONCE(msk->pm.remote_deny_join_id0) &&
+ msk->pm.local_addr_used == 0 &&
+ mptcp_pm_get_add_addr_accept_max(msk) == 0 &&
+ msk->pm.subflows < mptcp_pm_get_subflows_max(msk);
+}
+
void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk);
static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb)