The quilt patch titled
Subject: kasan: remove vmalloc_percpu test
has been removed from the -mm tree. Its filename was
kasan-remove-vmalloc_percpu-test.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Andrey Konovalov <andreyknvl(a)gmail.com>
Subject: kasan: remove vmalloc_percpu test
Date: Tue, 22 Oct 2024 18:07:06 +0200
Commit 1a2473f0cbc0 ("kasan: improve vmalloc tests") added the
vmalloc_percpu KASAN test with the assumption that __alloc_percpu always
uses vmalloc internally, which is tagged by KASAN.
However, __alloc_percpu might allocate memory from the first per-CPU
chunk, which is not allocated via vmalloc(). As a result, the test might
fail.
Remove the test until proper KASAN annotation for the per-CPU allocated
are added; tracked in https://bugzilla.kernel.org/show_bug.cgi?id=215019.
Link: https://lkml.kernel.org/r/20241022160706.38943-1-andrey.konovalov@linux.dev
Fixes: 1a2473f0cbc0 ("kasan: improve vmalloc tests")
Signed-off-by: Andrey Konovalov <andreyknvl(a)gmail.com>
Reported-by: Samuel Holland <samuel.holland(a)sifive.com>
Link: https://lore.kernel.org/all/4a245fff-cc46-44d1-a5f9-fd2f1c3764ae@sifive.com/
Reported-by: Sabyrzhan Tasbolatov <snovitoll(a)gmail.com>
Link: https://lore.kernel.org/all/CACzwLxiWzNqPBp4C1VkaXZ2wDwvY3yZeetCi1TLGFipKW7…
Cc: Alexander Potapenko <glider(a)google.com>
Cc: Andrey Ryabinin <ryabinin.a.a(a)gmail.com>
Cc: Dmitry Vyukov <dvyukov(a)google.com>
Cc: Marco Elver <elver(a)google.com>
Cc: Sabyrzhan Tasbolatov <snovitoll(a)gmail.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/kasan/kasan_test_c.c | 27 ---------------------------
1 file changed, 27 deletions(-)
--- a/mm/kasan/kasan_test_c.c~kasan-remove-vmalloc_percpu-test
+++ a/mm/kasan/kasan_test_c.c
@@ -1810,32 +1810,6 @@ static void vm_map_ram_tags(struct kunit
free_pages((unsigned long)p_ptr, 1);
}
-static void vmalloc_percpu(struct kunit *test)
-{
- char __percpu *ptr;
- int cpu;
-
- /*
- * This test is specifically crafted for the software tag-based mode,
- * the only tag-based mode that poisons percpu mappings.
- */
- KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS);
-
- ptr = __alloc_percpu(PAGE_SIZE, PAGE_SIZE);
-
- for_each_possible_cpu(cpu) {
- char *c_ptr = per_cpu_ptr(ptr, cpu);
-
- KUNIT_EXPECT_GE(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_MIN);
- KUNIT_EXPECT_LT(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_KERNEL);
-
- /* Make sure that in-bounds accesses don't crash the kernel. */
- *c_ptr = 0;
- }
-
- free_percpu(ptr);
-}
-
/*
* Check that the assigned pointer tag falls within the [KASAN_TAG_MIN,
* KASAN_TAG_KERNEL) range (note: excluding the match-all tag) for tag-based
@@ -2023,7 +1997,6 @@ static struct kunit_case kasan_kunit_tes
KUNIT_CASE(vmalloc_oob),
KUNIT_CASE(vmap_tags),
KUNIT_CASE(vm_map_ram_tags),
- KUNIT_CASE(vmalloc_percpu),
KUNIT_CASE(match_all_not_assigned),
KUNIT_CASE(match_all_ptr_tag),
KUNIT_CASE(match_all_mem_tag),
_
Patches currently in -mm which might be from andreyknvl(a)gmail.com are
From: Rick Edgecombe <rick.p.edgecombe(a)intel.com>
[ Upstream commit 03f5a999adba062456c8c818a683beb1b498983a ]
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
VMBus code could free decrypted pages if set_memory_encrypted()/decrypted()
fails. Leak the pages if this happens.
Signed-off-by: Rick Edgecombe <rick.p.edgecombe(a)intel.com>
Signed-off-by: Michael Kelley <mhklinux(a)outlook.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy(a)linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Link: https://lore.kernel.org/r/20240311161558.1310-2-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu(a)kernel.org>
Message-ID: <20240311161558.1310-2-mhklinux(a)outlook.com>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
[Xiangyu: bp to fix CVE-2024-36913, resolved minor conflicts]
Signed-off-by: Xiangyu Chen <xiangyu.chen(a)windriver.com>
---
drivers/hv/connection.c | 66 ++++++++++++++++++++++++++---------------
1 file changed, 42 insertions(+), 24 deletions(-)
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index da51b50787df..23fb0df9d350 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -243,8 +243,17 @@ int vmbus_connect(void)
ret |= set_memory_decrypted((unsigned long)
vmbus_connection.monitor_pages[1],
1);
- if (ret)
+ if (ret) {
+ /*
+ * If set_memory_decrypted() fails, the encryption state
+ * of the memory is unknown. So leak the memory instead
+ * of risking returning decrypted memory to the free list.
+ * For simplicity, always handle both pages the same.
+ */
+ vmbus_connection.monitor_pages[0] = NULL;
+ vmbus_connection.monitor_pages[1] = NULL;
goto cleanup;
+ }
/*
* Isolation VM with AMD SNP needs to access monitor page via
@@ -377,30 +386,39 @@ void vmbus_disconnect(void)
}
if (hv_is_isolation_supported()) {
- /*
- * memunmap() checks input address is ioremap address or not
- * inside. It doesn't unmap any thing in the non-SNP CVM and
- * so not check CVM type here.
- */
- memunmap(vmbus_connection.monitor_pages[0]);
- memunmap(vmbus_connection.monitor_pages[1]);
-
- set_memory_encrypted((unsigned long)
- vmbus_connection.monitor_pages_original[0],
- 1);
- set_memory_encrypted((unsigned long)
- vmbus_connection.monitor_pages_original[1],
- 1);
- }
+ if(vmbus_connection.monitor_pages[0]) {
+ /*
+ * memunmap() checks input address is ioremap address or not
+ * inside. It doesn't unmap any thing in the non-SNP CVM and
+ * so not check CVM type here.
+ */
+ memunmap(vmbus_connection.monitor_pages[0]);
+ if (!set_memory_encrypted((unsigned long)
+ vmbus_connection.monitor_pages_original[0], 1))
+ hv_free_hyperv_page((unsigned long)vmbus_connection.monitor_pages[0]);
+ vmbus_connection.monitor_pages_original[0] =
+ vmbus_connection.monitor_pages[0] = NULL;
+ }
+
+ if(vmbus_connection.monitor_pages[1]) {
+ memunmap(vmbus_connection.monitor_pages[1]);
+ if (!set_memory_encrypted((unsigned long)
+ vmbus_connection.monitor_pages_original[1], 1))
+ hv_free_hyperv_page((unsigned long)vmbus_connection.monitor_pages[1]);
+ vmbus_connection.monitor_pages_original[1] =
+ vmbus_connection.monitor_pages[1] = NULL;
+ }
+ } else {
- hv_free_hyperv_page((unsigned long)
- vmbus_connection.monitor_pages_original[0]);
- hv_free_hyperv_page((unsigned long)
- vmbus_connection.monitor_pages_original[1]);
- vmbus_connection.monitor_pages_original[0] =
- vmbus_connection.monitor_pages[0] = NULL;
- vmbus_connection.monitor_pages_original[1] =
- vmbus_connection.monitor_pages[1] = NULL;
+ hv_free_hyperv_page((unsigned long)
+ vmbus_connection.monitor_pages_original[0]);
+ hv_free_hyperv_page((unsigned long)
+ vmbus_connection.monitor_pages_original[1]);
+ vmbus_connection.monitor_pages_original[0] =
+ vmbus_connection.monitor_pages[0] = NULL;
+ vmbus_connection.monitor_pages_original[1] =
+ vmbus_connection.monitor_pages[1] = NULL;
+ }
}
/*
--
2.43.0
Setting TPM_CHIP_FLAG_SUSPENDED in the end of tpm_pm_suspend() can be racy
according to the bug report, as this leaves window for tpm_hwrng_read() to
be called while the operation is in progress.
To address this, lock the TPM chip before checking any possible flags.
This will guarantee that tpm_hwrng_read() and tpm_pm_suspend() won't
conflict with each other.
Cc: stable(a)vger.kernel.org # v6.4+
Fixes: 99d464506255 ("tpm: Prevent hwrng from activating during resume")
Reported-by: Mike Seo <mikeseohyungjin(a)gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219383
Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org>
---
v2:
- Addressed my own remark:
https://lore.kernel.org/linux-integrity/D59JAI6RR2CD.G5E5T4ZCZ49W@kernel.or…
---
drivers/char/tpm/tpm-interface.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 8134f002b121..e37fcf9361bc 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -370,6 +370,13 @@ int tpm_pm_suspend(struct device *dev)
if (!chip)
return -ENODEV;
+ rc = tpm_try_get_ops(chip);
+ if (rc) {
+ /* Can be safely set out of locks, as no action cannot race: */
+ chip->flags |= TPM_CHIP_FLAG_SUSPENDED;
+ goto out;
+ }
+
if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
goto suspended;
@@ -377,23 +384,22 @@ int tpm_pm_suspend(struct device *dev)
!pm_suspend_via_firmware())
goto suspended;
- rc = tpm_try_get_ops(chip);
- if (!rc) {
- if (chip->flags & TPM_CHIP_FLAG_TPM2) {
- tpm2_end_auth_session(chip);
- tpm2_shutdown(chip, TPM2_SU_STATE);
- } else {
- rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
- }
-
- tpm_put_ops(chip);
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ tpm2_end_auth_session(chip);
+ tpm2_shutdown(chip, TPM2_SU_STATE);
+ goto suspended;
}
+ rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
+
suspended:
chip->flags |= TPM_CHIP_FLAG_SUSPENDED;
+ tpm_put_ops(chip);
+out:
if (rc)
dev_err(dev, "Ignoring error %d while suspending\n", rc);
+
return 0;
}
EXPORT_SYMBOL_GPL(tpm_pm_suspend);
--
2.47.0
Do not continue on tpm2_create_primary() failure in tpm2_load_null().
Cc: stable(a)vger.kernel.org # v6.10+
Fixes: eb24c9788cd9 ("tpm: disable the TPM if NULL name changes")
Reviewed-by: Stefan Berger <stefanb(a)linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org>
---
v8:
- Fix stray character in a log message.
v7:
- No changes.
v6:
- Address Stefan's remark:
https://lore.kernel.org/linux-integrity/def4ec2d-584b-405f-9d5e-99267013c3c…
v5:
- Fix the TPM error code leak from tpm2_load_context().
v4:
- No changes.
v3:
- Update log messages. Previously the log message incorrectly stated
on load failure that integrity check had been failed, even tho the
check is done *after* the load operation.
v2:
- Refined the commit message.
- Reverted tpm2_create_primary() changes. They are not required if
tmp_null_key is used as the parameter.
---
drivers/char/tpm/tpm2-sessions.c | 44 +++++++++++++++++---------------
1 file changed, 24 insertions(+), 20 deletions(-)
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index a0306126e86c..950a3e48293b 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -915,33 +915,37 @@ static int tpm2_parse_start_auth_session(struct tpm2_auth *auth,
static int tpm2_load_null(struct tpm_chip *chip, u32 *null_key)
{
- int rc;
unsigned int offset = 0; /* dummy offset for null seed context */
u8 name[SHA256_DIGEST_SIZE + 2];
+ u32 tmp_null_key;
+ int rc;
rc = tpm2_load_context(chip, chip->null_key_context, &offset,
- null_key);
- if (rc != -EINVAL)
- return rc;
+ &tmp_null_key);
+ if (rc != -EINVAL) {
+ if (!rc)
+ *null_key = tmp_null_key;
+ goto err;
+ }
- /* an integrity failure may mean the TPM has been reset */
- dev_err(&chip->dev, "NULL key integrity failure!\n");
- /* check the null name against what we know */
- tpm2_create_primary(chip, TPM2_RH_NULL, NULL, name);
- if (memcmp(name, chip->null_key_name, sizeof(name)) == 0)
- /* name unchanged, assume transient integrity failure */
- return rc;
- /*
- * Fatal TPM failure: the NULL seed has actually changed, so
- * the TPM must have been illegally reset. All in-kernel TPM
- * operations will fail because the NULL primary can't be
- * loaded to salt the sessions, but disable the TPM anyway so
- * userspace programmes can't be compromised by it.
- */
- dev_err(&chip->dev, "NULL name has changed, disabling TPM due to interference\n");
+ /* Try to re-create null key, given the integrity failure: */
+ rc = tpm2_create_primary(chip, TPM2_RH_NULL, &tmp_null_key, name);
+ if (rc)
+ goto err;
+
+ /* Return null key if the name has not been changed: */
+ if (!memcmp(name, chip->null_key_name, sizeof(name))) {
+ *null_key = tmp_null_key;
+ return 0;
+ }
+
+ /* Deduce from the name change TPM interference: */
+ dev_err(&chip->dev, "null key integrity check failed\n");
+ tpm2_flush_context(chip, tmp_null_key);
chip->flags |= TPM_CHIP_FLAG_DISABLE;
- return rc;
+err:
+ return rc ? -ENODEV : 0;
}
/**
--
2.47.0
The patch titled
Subject: mm/mlock: set the correct prev on failure
has been added to the -mm mm-unstable branch. Its filename is
mm-mlock-set-the-correct-prev-on-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-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: Wei Yang <richard.weiyang(a)gmail.com>
Subject: mm/mlock: set the correct prev on failure
Date: Sun, 27 Oct 2024 12:33:21 +0000
After commit 94d7d9233951 ("mm: abstract the vma_merge()/split_vma()
pattern for mprotect() et al."), if vma_modify_flags() return error, the
vma is set to an error code. This will lead to an invalid prev be
returned.
Generally this shouldn't matter as the caller should treat an error as
indicating state is now invalidated, however unfortunately
apply_mlockall_flags() does not check for errors and assumes that
mlock_fixup() correctly maintains prev even if an error were to occur.
This patch fixes that assumption.
[lorenzo.stoakes(a)oracle.com: provide a better fix and rephrase the log]
Link: https://lkml.kernel.org/r/20241027123321.19511-1-richard.weiyang@gmail.com
Fixes: 94d7d9233951 ("mm: abstract the vma_merge()/split_vma() pattern for mprotect() et al.")
Signed-off-by: Wei Yang <richard.weiyang(a)gmail.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett(a)Oracle.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: Jann Horn <jannh(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/mlock.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/mm/mlock.c~mm-mlock-set-the-correct-prev-on-failure
+++ a/mm/mlock.c
@@ -725,14 +725,17 @@ static int apply_mlockall_flags(int flag
}
for_each_vma(vmi, vma) {
+ int error;
vm_flags_t newflags;
newflags = vma->vm_flags & ~VM_LOCKED_MASK;
newflags |= to_add;
- /* Ignore errors */
- mlock_fixup(&vmi, vma, &prev, vma->vm_start, vma->vm_end,
- newflags);
+ error = mlock_fixup(&vmi, vma, &prev, vma->vm_start, vma->vm_end,
+ newflags);
+ /* Ignore errors, but prev needs fixing up. */
+ if (error)
+ prev = vma;
cond_resched();
}
out:
_
Patches currently in -mm which might be from richard.weiyang(a)gmail.com are
maple_tree-i-is-always-less-than-or-equal-to-mas_end.patch
maple_tree-goto-complete-directly-on-a-pivot-of-0.patch
maple_tree-remove-maple_big_nodeparent.patch
maple_tree-memset-maple_big_node-as-a-whole.patch
maple_tree-root-node-could-be-handled-by-p_slot-too.patch
maple_tree-clear-request_count-for-new-allocated-one.patch
maple_tree-total-is-not-changed-for-nomem_one-case.patch
maple_tree-simplify-mas_push_node.patch
maple_tree-calculate-new_end-when-needed.patch
maple_tree-remove-sanity-check-from-mas_wr_slot_store.patch
mm-vma-the-pgoff-is-correct-if-can_merge_right.patch
mm-mlock-set-the-correct-prev-on-failure.patch
This series releases the 'soc' device_node when it is no longer required
by adding the missing calls to of_node_put() to make the fix compatible
with all affected stable kernels. Then, the more robust approach via
cleanup attribute is used to simplify the handling and prevent issues if
the loop gets new execution paths.
These issues were found while analyzing the code, and the patches have
been successfully compiled, but not tested on real hardware as I don't
have access to it. Any volunteering for testing is always more than
welcome.
Signed-off-by: Javier Carrasco <javier.carrasco.cruz(a)gmail.com>
---
Javier Carrasco (2):
clk: renesas: cpg-mssr: fix 'soc' node handling in cpg_mssr_reserved_init()
clk: renesas: cpg-mssr: automate 'soc' node release in cpg_mssr_reserved_init()
drivers/clk/renesas/renesas-cpg-mssr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
---
base-commit: 86e3904dcdc7e70e3257fc1de294a1b75f3d8d04
change-id: 20241031-clk-renesas-cpg-mssr-cleanup-1933df63bc9c
Best regards,
--
Javier Carrasco <javier.carrasco.cruz(a)gmail.com>
From: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Apparently using non-posted DSB writes to update the legacy
LUT can cause CPU MMIO accesses to fail on TGL. Stop using
them for the legacy LUT updates, and instead switch to using
the double write approach (which is the other empirically
found workaround for the issue of DSB failing to correctly
update the legacy LUT).
Cc: stable(a)vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/12494
Fixes: 25ea3411bd23 ("drm/i915/dsb: Use non-posted register writes for legacy LUT")
Signed-off-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
---
drivers/gpu/drm/i915/display/intel_color.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
index 174753625bca..aa50ecaf368d 100644
--- a/drivers/gpu/drm/i915/display/intel_color.c
+++ b/drivers/gpu/drm/i915/display/intel_color.c
@@ -1357,19 +1357,19 @@ static void ilk_load_lut_8(const struct intel_crtc_state *crtc_state,
lut = blob->data;
/*
- * DSB fails to correctly load the legacy LUT
- * unless we either write each entry twice,
- * or use non-posted writes
+ * DSB fails to correctly load the legacy LUT unless
+ * we either write each entry twice, or use non-posted
+ * writes. However using non-posted writes can cause
+ * CPU MMIO accesses to fail on TGL, so we choose to
+ * use the double write approach.
*/
- if (crtc_state->dsb_color_vblank)
- intel_dsb_nonpost_start(crtc_state->dsb_color_vblank);
-
- for (i = 0; i < 256; i++)
+ for (i = 0; i < 256; i++) {
ilk_lut_write(crtc_state, LGC_PALETTE(pipe, i),
i9xx_lut_8(&lut[i]));
-
- if (crtc_state->dsb_color_vblank)
- intel_dsb_nonpost_end(crtc_state->dsb_color_vblank);
+ if (crtc_state->dsb_color_vblank)
+ ilk_lut_write(crtc_state, LGC_PALETTE(pipe, i),
+ i9xx_lut_8(&lut[i]));
+ }
}
static void ilk_load_lut_10(const struct intel_crtc_state *crtc_state,
--
2.45.2
When we enter a signal handler we exit streaming mode in order to ensure
that signal handlers can run normal FPSIMD code, and while we're at it we
also clear PSTATE.ZA. Currently the code in setup_return() updates both the
in memory copy of the state and the register state. Not only is this
redundant it can also lead to corruption if we are preempted.
Consider two tasks on one CPU:
A: Begins signal entry in kernel mode, is preempted prior to SMSTOP.
B: Using SM and/or ZA in userspace with register state current on the
CPU, is preempted.
A: Scheduled in, no register state changes made as in kernel mode.
A: Executes SMSTOP, modifying live register state.
A: Scheduled out.
B: Scheduled in, fpsimd_thread_switch() sees the register state on the
CPU is tracked as being that for task B so the state is not reloaded
prior to returning to userspace.
Task B is now running with SM and ZA incorrectly cleared.
Fix this by check TIF_FOREIGN_FPSTATE and only updating one of the live
register context or the in memory copy when entering a signal handler.
Since this needs to happen atomically and all code that atomically
accesses FP state is in fpsimd.c also move the code there to ensure
consistency.
This race has been observed intermittently with fp-stress, especially
with preempt disabled.
Fixes: 40a8e87bb3285 ("arm64/sme: Disable ZA and streaming mode when handling signals")
Signed-off-by: Mark Brown <broonie(a)kernel.org>
Cc: stable(a)vger.kernel.org
---
arch/arm64/include/asm/fpsimd.h | 1 +
arch/arm64/kernel/fpsimd.c | 30 ++++++++++++++++++++++++++++++
arch/arm64/kernel/signal.c | 19 +------------------
3 files changed, 32 insertions(+), 18 deletions(-)
diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h
index f2a84efc361858d4deda99faf1967cc7cac386c1..09af7cfd9f6c2cec26332caa4c254976e117b1bf 100644
--- a/arch/arm64/include/asm/fpsimd.h
+++ b/arch/arm64/include/asm/fpsimd.h
@@ -76,6 +76,7 @@ extern void fpsimd_load_state(struct user_fpsimd_state *state);
extern void fpsimd_thread_switch(struct task_struct *next);
extern void fpsimd_flush_thread(void);
+extern void fpsimd_enter_sighandler(void);
extern void fpsimd_signal_preserve_current_state(void);
extern void fpsimd_preserve_current_state(void);
extern void fpsimd_restore_current_state(void);
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 77006df20a75aee7c991cf116b6d06bfe953d1a4..e6b086dc09f21e7f30df32ab4f6875b53c4228fd 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -1693,6 +1693,36 @@ void fpsimd_signal_preserve_current_state(void)
sve_to_fpsimd(current);
}
+/*
+ * Called by the signal handling code when preparing current to enter
+ * a signal handler. Currently this only needs to take care of exiting
+ * streaming mode and clearing ZA on SME systems.
+ */
+void fpsimd_enter_sighandler(void)
+{
+ if (!system_supports_sme())
+ return;
+
+ get_cpu_fpsimd_context();
+
+ if (test_thread_flag(TIF_FOREIGN_FPSTATE)) {
+ /* Exiting streaming mode zeros the FPSIMD state */
+ if (current->thread.svcr & SVCR_SM_MASK) {
+ memset(¤t->thread.uw.fpsimd_state, 0,
+ sizeof(current->thread.uw.fpsimd_state));
+ current->thread.fp_type = FP_STATE_FPSIMD;
+ }
+
+ current->thread.svcr &= ~(SVCR_ZA_MASK |
+ SVCR_SM_MASK);
+ } else {
+ /* The register state is current, just update it. */
+ sme_smstop();
+ }
+
+ put_cpu_fpsimd_context();
+}
+
/*
* Called by KVM when entering the guest.
*/
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 5619869475304776fc005fe24a385bf86bfdd253..fe07d0bd9f7978d73973f07ce38b7bdd7914abb2 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -1218,24 +1218,7 @@ static void setup_return(struct pt_regs *regs, struct k_sigaction *ka,
/* TCO (Tag Check Override) always cleared for signal handlers */
regs->pstate &= ~PSR_TCO_BIT;
- /* Signal handlers are invoked with ZA and streaming mode disabled */
- if (system_supports_sme()) {
- /*
- * If we were in streaming mode the saved register
- * state was SVE but we will exit SM and use the
- * FPSIMD register state - flush the saved FPSIMD
- * register state in case it gets loaded.
- */
- if (current->thread.svcr & SVCR_SM_MASK) {
- memset(¤t->thread.uw.fpsimd_state, 0,
- sizeof(current->thread.uw.fpsimd_state));
- current->thread.fp_type = FP_STATE_FPSIMD;
- }
-
- current->thread.svcr &= ~(SVCR_ZA_MASK |
- SVCR_SM_MASK);
- sme_smstop();
- }
+ fpsimd_enter_sighandler();
if (system_supports_poe())
write_sysreg_s(POR_EL0_INIT, SYS_POR_EL0);
---
base-commit: 8e929cb546ee42c9a61d24fae60605e9e3192354
change-id: 20241023-arm64-fp-sme-sigentry-a2bd7187e71b
Best regards,
--
Mark Brown <broonie(a)kernel.org>