Hello,
as described in the commit log of the two commits the rtc-mt6397 driver
relies on these fixes as soon as it should store dates later than
2027-12-31. On one of the patches has a Fixes line, so this submission
is done to ensure that both patches are backported.
The patches sent in reply to this mail are (trivial) backports to
v6.15.1, they should get backported to the older stable kernels, too, to
(somewhat) ensure that in 2028 no surprises happen. `git am` is able to
apply the patches as is to 6.14.y, 6.12.y, 6.6.y, 6.1.y and 5.15.y.
5.10 and 5.4 need an adaption, I didn't look into that yet but can
follow up with backports for these.
The two fixes were accompanied by 3 test updates:
46351921cbe1 ("rtc: test: Emit the seconds-since-1970 value instead of days-since-1970")
da62b49830f8 ("rtc: test: Also test time and wday outcome of rtc_time64_to_tm()")
ccb2dba3c19f ("rtc: test: Test date conversion for dates starting in 1900")
that cover one of the patches. Would you consider it sensible to
backport these, too?
Best regards
Uwe
Alexandre Mergnat (2):
rtc: Make rtc_time64_to_tm() support dates before 1970
rtc: Fix offset calculation for .start_secs < 0
drivers/rtc/class.c | 2 +-
drivers/rtc/lib.c | 24 +++++++++++++++++++-----
2 files changed, 20 insertions(+), 6 deletions(-)
base-commit: 3ef49626da6dd67013fc2cf0a4e4c9e158bb59f7
--
2.47.2
The patch titled
Subject: mm: close theoretical race where stale TLB entries could linger
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-close-theoretical-race-where-stale-tlb-entries-could-linger.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Ryan Roberts <ryan.roberts(a)arm.com>
Subject: mm: close theoretical race where stale TLB entries could linger
Date: Fri, 6 Jun 2025 10:28:07 +0100
Commit 3ea277194daa ("mm, mprotect: flush TLB if potentially racing with a
parallel reclaim leaving stale TLB entries") described a theoretical race
as such:
"""
Nadav Amit identified a theoretical race between page reclaim and mprotect
due to TLB flushes being batched outside of the PTL being held.
He described the race as follows:
CPU0 CPU1
---- ----
user accesses memory using RW PTE
[PTE now cached in TLB]
try_to_unmap_one()
==> ptep_get_and_clear()
==> set_tlb_ubc_flush_pending()
mprotect(addr, PROT_READ)
==> change_pte_range()
==> [ PTE non-present - no flush ]
user writes using cached RW PTE
...
try_to_unmap_flush()
The same type of race exists for reads when protecting for PROT_NONE and
also exists for operations that can leave an old TLB entry behind such as
munmap, mremap and madvise.
"""
The solution was to introduce flush_tlb_batched_pending() and call it
under the PTL from mprotect/madvise/munmap/mremap to complete any pending
tlb flushes.
However, while madvise_free_pte_range() and
madvise_cold_or_pageout_pte_range() were both retro-fitted to call
flush_tlb_batched_pending() immediately after initially acquiring the PTL,
they both temporarily release the PTL to split a large folio if they
stumble upon one. In this case, where re-acquiring the PTL
flush_tlb_batched_pending() must be called again, but it previously was
not. Let's fix that.
There are 2 Fixes: tags here: the first is the commit that fixed
madvise_free_pte_range(). The second is the commit that added
madvise_cold_or_pageout_pte_range(), which looks like it copy/pasted the
faulty pattern from madvise_free_pte_range().
This is a theoretical bug discovered during code review.
Link: https://lkml.kernel.org/r/20250606092809.4194056-1-ryan.roberts@arm.com
Fixes: 3ea277194daa ("mm, mprotect: flush TLB if potentially racing with a parallel reclaim leaving stale TLB entries")
Fixes: 9c276cc65a58 ("mm: introduce MADV_COLD")
Signed-off-by: Ryan Roberts <ryan.roberts(a)arm.com>
Reviewed-by: Jann Horn <jannh(a)google.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Mel Gorman <mgorman <mgorman(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/madvise.c | 2 ++
1 file changed, 2 insertions(+)
--- a/mm/madvise.c~mm-close-theoretical-race-where-stale-tlb-entries-could-linger
+++ a/mm/madvise.c
@@ -508,6 +508,7 @@ restart:
pte_offset_map_lock(mm, pmd, addr, &ptl);
if (!start_pte)
break;
+ flush_tlb_batched_pending(mm);
arch_enter_lazy_mmu_mode();
if (!err)
nr = 0;
@@ -741,6 +742,7 @@ static int madvise_free_pte_range(pmd_t
start_pte = pte;
if (!start_pte)
break;
+ flush_tlb_batched_pending(mm);
arch_enter_lazy_mmu_mode();
if (!err)
nr = 0;
_
Patches currently in -mm which might be from ryan.roberts(a)arm.com are
mm-close-theoretical-race-where-stale-tlb-entries-could-linger.patch
The patch titled
Subject: mm/vma: reset VMA iterator on commit_merge() OOM failure
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-vma-reset-vma-iterator-on-commit_merge-oom-failure.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Subject: mm/vma: reset VMA iterator on commit_merge() OOM failure
Date: Fri, 6 Jun 2025 13:50:32 +0100
While an OOM failure in commit_merge() isn't really feasible due to the
allocation which might fail (a maple tree pre-allocation) being 'too small
to fail', we do need to handle this case correctly regardless.
In vma_merge_existing_range(), we can theoretically encounter failures
which result in an OOM error in two ways - firstly dup_anon_vma() might
fail with an OOM error, and secondly commit_merge() failing, ultimately,
to pre-allocate a maple tree node.
The abort logic for dup_anon_vma() resets the VMA iterator to the initial
range, ensuring that any logic looping on this iterator will correctly
proceed to the next VMA.
However the commit_merge() abort logic does not do the same thing. This
resulted in a syzbot report occurring because mlockall() iterates through
VMAs, is tolerant of errors, but ended up with an incorrect previous VMA
being specified due to incorrect iterator state.
While making this change, it became apparent we are duplicating logic -
the logic introduced in commit 41e6ddcaa0f1 ("mm/vma: add give_up_on_oom
option on modify/merge, use in uffd release") duplicates the
vmg->give_up_on_oom check in both abort branches.
Additionally, we observe that we can perform the anon_dup check safely on
dup_anon_vma() failure, as this will not be modified should this call
fail.
Finally, we need to reset the iterator in both cases, so now we can simply
use the exact same code to abort for both.
We remove the VM_WARN_ON(err != -ENOMEM) as it would be silly for this to
be otherwise and it allows us to implement the abort check more neatly.
Link: https://lkml.kernel.org/r/20250606125032.164249-1-lorenzo.stoakes@oracle.com
Fixes: 47b16d0462a4 ("mm: abort vma_modify() on merge out of memory failure")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reported-by: syzbot+d16409ea9ecc16ed261a(a)syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-mm/6842cc67.a00a0220.29ac89.003b.GAE@google.c…
Reviewed-by: Pedro Falcato <pfalcato(a)suse.de>
Reviewed-by: Vlastimil Babka <vbabka(a)suse.cz>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/vma.c | 22 ++++------------------
1 file changed, 4 insertions(+), 18 deletions(-)
--- a/mm/vma.c~mm-vma-reset-vma-iterator-on-commit_merge-oom-failure
+++ a/mm/vma.c
@@ -961,26 +961,9 @@ static __must_check struct vm_area_struc
err = dup_anon_vma(next, middle, &anon_dup);
}
- if (err)
+ if (err || commit_merge(vmg))
goto abort;
- err = commit_merge(vmg);
- if (err) {
- VM_WARN_ON(err != -ENOMEM);
-
- if (anon_dup)
- unlink_anon_vmas(anon_dup);
-
- /*
- * We've cleaned up any cloned anon_vma's, no VMAs have been
- * modified, no harm no foul if the user requests that we not
- * report this and just give up, leaving the VMAs unmerged.
- */
- if (!vmg->give_up_on_oom)
- vmg->state = VMA_MERGE_ERROR_NOMEM;
- return NULL;
- }
-
khugepaged_enter_vma(vmg->target, vmg->flags);
vmg->state = VMA_MERGE_SUCCESS;
return vmg->target;
@@ -989,6 +972,9 @@ abort:
vma_iter_set(vmg->vmi, start);
vma_iter_load(vmg->vmi);
+ if (anon_dup)
+ unlink_anon_vmas(anon_dup);
+
/*
* This means we have failed to clone anon_vma's correctly, but no
* actual changes to VMAs have occurred, so no harm no foul - if the
_
Patches currently in -mm which might be from lorenzo.stoakes(a)oracle.com are
mm-vma-reset-vma-iterator-on-commit_merge-oom-failure.patch
docs-mm-expand-vma-doc-to-highlight-pte-freeing-non-vma-traversal.patch
mm-ksm-have-ksm-vma-checks-not-require-a-vma-pointer.patch
mm-ksm-refer-to-special-vmas-via-vm_special-in-ksm_compatible.patch
mm-prevent-ksm-from-breaking-vma-merging-for-new-vmas.patch
tools-testing-selftests-add-vma-merge-tests-for-ksm-merge.patch
mm-pagewalk-split-walk_page_range_novma-into-kernel-user-parts.patch
fxls8962af_fifo_flush() uses indio_dev->active_scan_mask (with
iio_for_each_active_channel()) without making sure the indio_dev
stays in buffer mode.
There is a race if indio_dev exits buffer mode in the middle of the
interrupt that flushes the fifo. Fix this by calling
synchronize_irq() to ensure that no interrupt is currently running when
disabling buffer mode.
Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read
[...]
_find_first_bit_le from fxls8962af_fifo_flush+0x17c/0x290
fxls8962af_fifo_flush from fxls8962af_interrupt+0x80/0x178
fxls8962af_interrupt from irq_thread_fn+0x1c/0x7c
irq_thread_fn from irq_thread+0x110/0x1f4
irq_thread from kthread+0xe0/0xfc
kthread from ret_from_fork+0x14/0x2c
Fixes: 79e3a5bdd9ef ("iio: accel: fxls8962af: add hw buffered sampling")
Cc: stable(a)vger.kernel.org
Suggested-by: David Lechner <dlechner(a)baylibre.com>
Signed-off-by: Sean Nyekjaer <sean(a)geanix.com>
---
Changes in v2:
- As per David's suggestion; switched to use synchronize_irq() instead.
- Link to v1: https://lore.kernel.org/r/20250524-fxlsrace-v1-1-dec506dc87ae@geanix.com
---
drivers/iio/accel/fxls8962af-core.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/iio/accel/fxls8962af-core.c b/drivers/iio/accel/fxls8962af-core.c
index 6d23da3e7aa22c61f2d9348bb91d70cc5719a732..f2558fba491dffa78b26d47d2cd9f1f4d9811f54 100644
--- a/drivers/iio/accel/fxls8962af-core.c
+++ b/drivers/iio/accel/fxls8962af-core.c
@@ -866,6 +866,8 @@ static int fxls8962af_buffer_predisable(struct iio_dev *indio_dev)
if (ret)
return ret;
+ synchronize_irq(data->irq);
+
ret = __fxls8962af_fifo_set_mode(data, false);
if (data->enable_event)
---
base-commit: 5c3fcb36c92443a9a037683626a2e43d8825f783
change-id: 20250524-fxlsrace-f4d20e29fb29
Best regards,
--
Sean Nyekjaer <sean(a)geanix.com>
From: Ajay Agarwal <ajayagarwal(a)google.com>
[ Upstream commit 7447990137bf06b2aeecad9c6081e01a9f47f2aa ]
PCIe r6.2, sec 5.5.4, requires that:
If setting either or both of the enable bits for ASPM L1 PM Substates,
both ports must be configured as described in this section while ASPM L1
is disabled.
Previously, pcie_config_aspm_l1ss() assumed that "setting enable bits"
meant "setting them to 1", and it configured L1SS as follows:
- Clear L1SS enable bits
- Disable L1
- Configure L1SS enable bits as required
- Enable L1 if required
With this sequence, when disabling L1SS on an ARM A-core with a Synopsys
DesignWare PCIe core, the CPU occasionally hangs when reading
PCI_L1SS_CTL1, leading to a reboot when the CPU watchdog expires.
Move the L1 disable to the caller (pcie_config_aspm_link(), where L1 was
already enabled) so L1 is always disabled while updating the L1SS bits:
- Disable L1
- Clear L1SS enable bits
- Configure L1SS enable bits as required
- Enable L1 if required
Change pcie_aspm_cap_init() similarly.
Link: https://lore.kernel.org/r/20241007032917.872262-1-ajayagarwal@google.com
Signed-off-by: Ajay Agarwal <ajayagarwal(a)google.com>
[bhelgaas: comments, commit log, compute L1SS setting before config access]
Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com>
Tested-by: Johnny-CC Chang <Johnny-CC.Chang(a)mediatek.com>
Signed-off-by: Macpaul Lin <macpaul.lin(a)mediatek.com>
---
drivers/pci/pcie/aspm.c | 92 ++++++++++++++++++++++-------------------
1 file changed, 50 insertions(+), 42 deletions(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index cee2365e54b8..e943691bc931 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -805,6 +805,15 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
pcie_capability_read_word(parent, PCI_EXP_LNKCTL, &parent_lnkctl);
pcie_capability_read_word(child, PCI_EXP_LNKCTL, &child_lnkctl);
+ /* Disable L0s/L1 before updating L1SS config */
+ if (FIELD_GET(PCI_EXP_LNKCTL_ASPMC, child_lnkctl) ||
+ FIELD_GET(PCI_EXP_LNKCTL_ASPMC, parent_lnkctl)) {
+ pcie_capability_write_word(child, PCI_EXP_LNKCTL,
+ child_lnkctl & ~PCI_EXP_LNKCTL_ASPMC);
+ pcie_capability_write_word(parent, PCI_EXP_LNKCTL,
+ parent_lnkctl & ~PCI_EXP_LNKCTL_ASPMC);
+ }
+
/*
* Setup L0s state
*
@@ -829,6 +838,13 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
aspm_l1ss_init(link);
+ /* Restore L0s/L1 if they were enabled */
+ if (FIELD_GET(PCI_EXP_LNKCTL_ASPMC, child_lnkctl) ||
+ FIELD_GET(PCI_EXP_LNKCTL_ASPMC, parent_lnkctl)) {
+ pcie_capability_write_word(parent, PCI_EXP_LNKCTL, parent_lnkctl);
+ pcie_capability_write_word(child, PCI_EXP_LNKCTL, child_lnkctl);
+ }
+
/* Save default state */
link->aspm_default = link->aspm_enabled;
@@ -845,25 +861,28 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
}
}
-/* Configure the ASPM L1 substates */
+/* Configure the ASPM L1 substates. Caller must disable L1 first. */
static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
{
- u32 val, enable_req;
+ u32 val;
struct pci_dev *child = link->downstream, *parent = link->pdev;
- enable_req = (link->aspm_enabled ^ state) & state;
+ val = 0;
+ if (state & PCIE_LINK_STATE_L1_1)
+ val |= PCI_L1SS_CTL1_ASPM_L1_1;
+ if (state & PCIE_LINK_STATE_L1_2)
+ val |= PCI_L1SS_CTL1_ASPM_L1_2;
+ if (state & PCIE_LINK_STATE_L1_1_PCIPM)
+ val |= PCI_L1SS_CTL1_PCIPM_L1_1;
+ if (state & PCIE_LINK_STATE_L1_2_PCIPM)
+ val |= PCI_L1SS_CTL1_PCIPM_L1_2;
/*
- * Here are the rules specified in the PCIe spec for enabling L1SS:
- * - When enabling L1.x, enable bit at parent first, then at child
- * - When disabling L1.x, disable bit at child first, then at parent
- * - When enabling ASPM L1.x, need to disable L1
- * (at child followed by parent).
- * - The ASPM/PCIPM L1.2 must be disabled while programming timing
+ * PCIe r6.2, sec 5.5.4, rules for enabling L1 PM Substates:
+ * - Clear L1.x enable bits at child first, then at parent
+ * - Set L1.x enable bits at parent first, then at child
+ * - ASPM/PCIPM L1.2 must be disabled while programming timing
* parameters
- *
- * To keep it simple, disable all L1SS bits first, and later enable
- * what is needed.
*/
/* Disable all L1 substates */
@@ -871,26 +890,6 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
PCI_L1SS_CTL1_L1SS_MASK, 0);
pci_clear_and_set_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
PCI_L1SS_CTL1_L1SS_MASK, 0);
- /*
- * If needed, disable L1, and it gets enabled later
- * in pcie_config_aspm_link().
- */
- if (enable_req & (PCIE_LINK_STATE_L1_1 | PCIE_LINK_STATE_L1_2)) {
- pcie_capability_clear_word(child, PCI_EXP_LNKCTL,
- PCI_EXP_LNKCTL_ASPM_L1);
- pcie_capability_clear_word(parent, PCI_EXP_LNKCTL,
- PCI_EXP_LNKCTL_ASPM_L1);
- }
-
- val = 0;
- if (state & PCIE_LINK_STATE_L1_1)
- val |= PCI_L1SS_CTL1_ASPM_L1_1;
- if (state & PCIE_LINK_STATE_L1_2)
- val |= PCI_L1SS_CTL1_ASPM_L1_2;
- if (state & PCIE_LINK_STATE_L1_1_PCIPM)
- val |= PCI_L1SS_CTL1_PCIPM_L1_1;
- if (state & PCIE_LINK_STATE_L1_2_PCIPM)
- val |= PCI_L1SS_CTL1_PCIPM_L1_2;
/* Enable what we need to enable */
pci_clear_and_set_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
@@ -937,21 +936,30 @@ static void pcie_config_aspm_link(struct pcie_link_state *link, u32 state)
dwstream |= PCI_EXP_LNKCTL_ASPM_L1;
}
+ /*
+ * Per PCIe r6.2, sec 5.5.4, setting either or both of the enable
+ * bits for ASPM L1 PM Substates must be done while ASPM L1 is
+ * disabled. Disable L1 here and apply new configuration after L1SS
+ * configuration has been completed.
+ *
+ * Per sec 7.5.3.7, when disabling ASPM L1, software must disable
+ * it in the Downstream component prior to disabling it in the
+ * Upstream component, and ASPM L1 must be enabled in the Upstream
+ * component prior to enabling it in the Downstream component.
+ *
+ * Sec 7.5.3.7 also recommends programming the same ASPM Control
+ * value for all functions of a multi-function device.
+ */
+ list_for_each_entry(child, &linkbus->devices, bus_list)
+ pcie_config_aspm_dev(child, 0);
+ pcie_config_aspm_dev(parent, 0);
+
if (link->aspm_capable & PCIE_LINK_STATE_L1SS)
pcie_config_aspm_l1ss(link, state);
- /*
- * Spec 2.0 suggests all functions should be configured the
- * same setting for ASPM. Enabling ASPM L1 should be done in
- * upstream component first and then downstream, and vice
- * versa for disabling ASPM L1. Spec doesn't mention L0S.
- */
- if (state & PCIE_LINK_STATE_L1)
- pcie_config_aspm_dev(parent, upstream);
+ pcie_config_aspm_dev(parent, upstream);
list_for_each_entry(child, &linkbus->devices, bus_list)
pcie_config_aspm_dev(child, dwstream);
- if (!(state & PCIE_LINK_STATE_L1))
- pcie_config_aspm_dev(parent, upstream);
link->aspm_enabled = state;
--
2.45.2
Hi,
I wanted to check if you’d be interested in acquiring the attendees list of UITP Summit - Hamburg 2025?
Event Overview:
Dates: 15 - 18 Jun 2025
Location: Hamburg, Germany
Attendees: 10,126
Exhibitors: 380
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If you're interested in the list, just reply "Send Counts and Cost"?
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Senior Marketing Manager
To unsubscribe, simply respond with “Not interested.”
Hi,
Please cherry-pick following 9 patches to 6.12:
525a3858aad73 accel/ivpu: Set 500 ns delay between power island TRICKLE and ENABLE
08eb99ce911d3 accel/ivpu: Do not fail on cmdq if failed to allocate preemption buffers
755fb86789165 accel/ivpu: Use whole user and shave ranges for preemption buffers
98110eb5924bd accel/ivpu: Increase MS info buffer size
c140244f0cfb9 accel/ivpu: Add initial Panther Lake support
88bdd1644ca28 accel/ivpu: Update power island delays
ce68f86c44513 accel/ivpu: Do not fail when more than 1 tile is fused
83b6fa5844b53 accel/ivpu: Increase DMA address range
e91191efe75a9 accel/ivpu: Move secondary preemption buffer allocation to DMA range
These add support for new Panther Lake HW.
They should apply without conflicts.
Thanks,
Jacek
IDT event delivery has a debug hole in which it does not generate #DB
upon returning to userspace before the first userspace instruction is
executed if the Trap Flag (TF) is set.
FRED closes this hole by introducing a software event flag, i.e., bit
17 of the augmented SS: if the bit is set and ERETU would result in
RFLAGS.TF = 1, a single-step trap will be pending upon completion of
ERETU.
However I overlooked properly setting and clearing the bit in different
situations. Thus when FRED is enabled, if the Trap Flag (TF) is set
without an external debugger attached, it can lead to an infinite loop
in the SIGTRAP handler. To avoid this, the software event flag in the
augmented SS must be cleared, ensuring that no single-step trap remains
pending when ERETU completes.
This patch set combines the fix [1] and its corresponding selftest [2]
(requested by Dave Hansen) into one patch set.
[1] https://lore.kernel.org/lkml/20250523050153.3308237-1-xin@zytor.com/
[2] https://lore.kernel.org/lkml/20250530230707.2528916-1-xin@zytor.com/
This patch set is based on tip/x86/urgent branch as of today.
Link to v4 of this patch set:
https://lore.kernel.org/lkml/20250605181020.590459-1-xin@zytor.com/
Changes in v5:
*) Accurately rephrase the shortlog (hpa).
*) Do "sub $-128, %rsp" rather than "add $128, %rsp", which is more
efficient in code size (hpa).
*) Add TB from Sohil.
*) Add Cc: stable(a)vger.kernel.org to all patches.
Xin Li (Intel) (2):
x86/fred/signal: Prevent immediate repeat of single step trap on
return from SIGTRAP handler
selftests/x86: Add a test to detect infinite sigtrap handler loop
arch/x86/include/asm/sighandling.h | 22 +++++
arch/x86/kernel/signal_32.c | 4 +
arch/x86/kernel/signal_64.c | 4 +
tools/testing/selftests/x86/Makefile | 2 +-
tools/testing/selftests/x86/sigtrap_loop.c | 98 ++++++++++++++++++++++
5 files changed, 129 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/x86/sigtrap_loop.c
base-commit: dd2922dcfaa3296846265e113309e5f7f138839f
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2.49.0