There appears to be a possible use after free with vdec_close().
The firmware will add buffer release work to the work queue through
HFI callbacks as a normal part of decoding. Randomly closing the
decoder device from userspace during normal decoding can incur
a read after free for inst.
Fix it by cancelling the work in vdec_close.
Cc: stable(a)vger.kernel.org
Fixes: af2c3834c ("media: venus: adding core part and helper functions")
Signed-off-by: Dikshita Agarwal <quic_dikshita(a)quicinc.com>
---
Changes since v2:
- fixed email id
Changes since v1:
- Added fixes and stable tags
drivers/media/platform/qcom/venus/vdec.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/media/platform/qcom/venus/vdec.c b/drivers/media/platform/qcom/venus/vdec.c
index 29130a9..56f8a25 100644
--- a/drivers/media/platform/qcom/venus/vdec.c
+++ b/drivers/media/platform/qcom/venus/vdec.c
@@ -1747,6 +1747,7 @@ static int vdec_close(struct file *file)
vdec_pm_get(inst);
+ cancel_work_sync(&inst->delayed_process_work);
v4l2_m2m_ctx_release(inst->m2m_ctx);
v4l2_m2m_release(inst->m2m_dev);
vdec_ctrl_deinit(inst);
--
2.7.4
There is an issue with ACPI overlay table removal specifically related
to I2C multiplexers.
Consider an ACPI SSDT Overlay that defines a PCA9548 I2C mux on an
existing I2C bus. When this table is loaded we see the creation of a
device for the overall PCA9548 chip and 8 further devices - one
i2c_adapter each for the mux channels. These are all bound to their
ACPI equivalents via an eventual invocation of acpi_bind_one().
When we unload the SSDT overlay we run into the problem. The ACPI
devices are deleted as normal via acpi_device_del_work_fn() and the
acpi_device_del_list.
However, the following warning and stack trace is output as the
deletion does not go smoothly:
------------[ cut here ]------------
kernfs: can not remove 'physical_node', no directory
WARNING: CPU: 1 PID: 11 at fs/kernfs/dir.c:1674 kernfs_remove_by_name_ns+0xb9/0xc0
Modules linked in:
CPU: 1 PID: 11 Comm: kworker/u128:0 Not tainted 6.8.0-rc6+ #1
Hardware name: congatec AG conga-B7E3/conga-B7E3, BIOS 5.13 05/16/2023
Workqueue: kacpi_hotplug acpi_device_del_work_fn
RIP: 0010:kernfs_remove_by_name_ns+0xb9/0xc0
Code: e4 00 48 89 ef e8 07 71 db ff 5b b8 fe ff ff ff 5d 41 5c 41 5d e9 a7 55 e4 00 0f 0b eb a6 48 c7 c7 f0 38 0d 9d e8 97 0a d5 ff <0f> 0b eb dc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffff9f864008fb28 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff8ef90a8d4940 RCX: 0000000000000000
RDX: ffff8f000e267d10 RSI: ffff8f000e25c780 RDI: ffff8f000e25c780
RBP: ffff8ef9186f9870 R08: 0000000000013ffb R09: 00000000ffffbfff
R10: 00000000ffffbfff R11: ffff8f000e0a0000 R12: ffff9f864008fb50
R13: ffff8ef90c93dd60 R14: ffff8ef9010d0958 R15: ffff8ef9186f98c8
FS: 0000000000000000(0000) GS:ffff8f000e240000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48f5253a08 CR3: 00000003cb82e000 CR4: 00000000003506f0
Call Trace:
<TASK>
? kernfs_remove_by_name_ns+0xb9/0xc0
? __warn+0x7c/0x130
? kernfs_remove_by_name_ns+0xb9/0xc0
? report_bug+0x171/0x1a0
? handle_bug+0x3c/0x70
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? kernfs_remove_by_name_ns+0xb9/0xc0
? kernfs_remove_by_name_ns+0xb9/0xc0
acpi_unbind_one+0x108/0x180
device_del+0x18b/0x490
? srso_return_thunk+0x5/0x5f
? srso_return_thunk+0x5/0x5f
device_unregister+0xd/0x30
i2c_del_adapter.part.0+0x1bf/0x250
i2c_mux_del_adapters+0xa1/0xe0
i2c_device_remove+0x1e/0x80
device_release_driver_internal+0x19a/0x200
bus_remove_device+0xbf/0x100
device_del+0x157/0x490
? __pfx_device_match_fwnode+0x10/0x10
? srso_return_thunk+0x5/0x5f
device_unregister+0xd/0x30
i2c_acpi_notify+0x10f/0x140
notifier_call_chain+0x58/0xd0
blocking_notifier_call_chain+0x3a/0x60
acpi_device_del_work_fn+0x85/0x1d0
process_one_work+0x134/0x2f0
worker_thread+0x2f0/0x410
? __pfx_worker_thread+0x10/0x10
kthread+0xe3/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2f/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
---[ end trace 0000000000000000 ]---
...
repeated 7 more times, 1 for each channel of the mux
...
The issue is that the binding of the ACPI devices to their peer I2C
adapters is not correctly cleaned up. Digging deeper into the issue we
see that the deletion order is such that the ACPI devices matching the
mux channel i2c adapters are deleted first during the SSDT overlay
removal. For each of the channels we see a call to i2c_acpi_notify()
with ACPI_RECONFIG_DEVICE_REMOVE but, because these devices are not
actually i2c_clients, nothing is done for them.
Later on, after each of the mux channels has been dealt with, we come
to delete the i2c_client representing the PCA9548 device. This is the
call stack we see above, whereby the kernel cleans up the i2c_client
including destruction of the mux and its channel adapters. At this
point we do attempt to unbind from the ACPI peers but those peers no
longer exist and so we hit the kernfs errors.
The fix is to augment i2c_acpi_notify() to handle i2c_adapters. But,
given that the life cycle of the adapters is linked to the i2c_client,
instead of deleting the i2c_adapters during the i2c_acpi_notify(), we
just trigger unbinding of the ACPI device from the adapter device, and
allow the clean up of the adapter to continue in the way it always has.
Signed-off-by: Hamish Martin <hamish.martin(a)alliedtelesis.co.nz>
Reviewed-by: Mika Westerberg <mika.westerberg(a)linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti(a)kernel.org>
Fixes: 525e6fabeae2 ("i2c / ACPI: add support for ACPI reconfigure notifications")
Cc: <stable(a)vger.kernel.org> # v4.8+
---
Notes:
v4:
Resolve Build failure noted by:
Linux Kernel Functional Testing <lkft(a)linaro.org>, and
kernel test robot <lkp(a)intel.com>
These failures led to revert of the v3 version of this patch that had been accepted earlier.
v3:
Add reviewed by tags (Mika Westerberg and Andi Shyti) and Fixes tag.
v2:
Moved long problem description from cover letter to commit description at Mika's suggestion
drivers/i2c/i2c-core-acpi.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index d6037a328669..14ae0cfc325e 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -445,6 +445,11 @@ static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
return i2c_find_device_by_fwnode(acpi_fwnode_handle(adev));
}
+static struct i2c_adapter *i2c_acpi_find_adapter_by_adev(struct acpi_device *adev)
+{
+ return i2c_find_adapter_by_fwnode(acpi_fwnode_handle(adev));
+}
+
static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
void *arg)
{
@@ -471,11 +476,17 @@ static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
break;
client = i2c_acpi_find_client_by_adev(adev);
- if (!client)
- break;
+ if (client) {
+ i2c_unregister_device(client);
+ put_device(&client->dev);
+ }
+
+ adapter = i2c_acpi_find_adapter_by_adev(adev);
+ if (adapter) {
+ acpi_unbind_one(&adapter->dev);
+ put_device(&adapter->dev);
+ }
- i2c_unregister_device(client);
- put_device(&client->dev);
break;
}
--
2.43.2
From: Dikshita Agarwal <quic_dikshita(a)quicinc.com>
There appears to be a possible use after free with vdec_close().
The firmware will add buffer release work to the work queue through
HFI callbacks as a normal part of decoding. Randomly closing the
decoder device from userspace during normal decoding can incur
a read after free for inst.
Fix it by cancelling the work in vdec_close.
Cc: stable(a)vger.kernel.org
Fixes: af2c3834c ("media: venus: adding core part and helper functions")
Signed-off-by: Dikshita Agarwal <quic_dikshita(a)quicinc.com>
---
Changes since v1:
- Added fixes and stable tags
drivers/media/platform/qcom/venus/vdec.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/media/platform/qcom/venus/vdec.c b/drivers/media/platform/qcom/venus/vdec.c
index 29130a9..56f8a25 100644
--- a/drivers/media/platform/qcom/venus/vdec.c
+++ b/drivers/media/platform/qcom/venus/vdec.c
@@ -1747,6 +1747,7 @@ static int vdec_close(struct file *file)
vdec_pm_get(inst);
+ cancel_work_sync(&inst->delayed_process_work);
v4l2_m2m_ctx_release(inst->m2m_ctx);
v4l2_m2m_release(inst->m2m_dev);
vdec_ctrl_deinit(inst);
--
2.7.4
The quilt patch titled
Subject: kexec: fix the unexpected kexec_dprintk() macro
has been removed from the -mm tree. Its filename was
kexec-fix-the-unexpected-kexec_dprintk-macro.patch
This patch was dropped because it was merged into the mm-nonmm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Baoquan He <bhe(a)redhat.com>
Subject: kexec: fix the unexpected kexec_dprintk() macro
Date: Tue, 9 Apr 2024 12:22:38 +0800
Jiri reported that the current kexec_dprintk() always prints out debugging
message whenever kexec/kdmmp loading is triggered. That is not wanted.
The debugging message is supposed to be printed out when 'kexec -s -d' is
specified for kexec/kdump loading.
After investigating, the reason is the current kexec_dprintk() takes
printk(KERN_INFO) or printk(KERN_DEBUG) depending on whether '-d' is
specified. However, distros usually have defaulg log level like below:
[~]# cat /proc/sys/kernel/printk
7 4 1 7
So, even though '-d' is not specified, printk(KERN_DEBUG) also always
prints out. I thought printk(KERN_DEBUG) is equal to pr_debug(), it's
not.
Fix it by changing to use pr_info() instead which are expected to work.
Link: https://lkml.kernel.org/r/20240409042238.1240462-1-bhe@redhat.com
Fixes: cbc2fe9d9cb2 ("kexec_file: add kexec_file flag to control debug printing")
Signed-off-by: Baoquan He <bhe(a)redhat.com>
Reported-by: Jiri Slaby <jirislaby(a)kernel.org>
Closes: https://lore.kernel.org/all/4c775fca-5def-4a2d-8437-7130b02722a2@kernel.org
Reviewed-by: Dave Young <dyoung(a)redhat.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/kexec.h | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
--- a/include/linux/kexec.h~kexec-fix-the-unexpected-kexec_dprintk-macro
+++ a/include/linux/kexec.h
@@ -461,10 +461,8 @@ static inline void arch_kexec_pre_free_p
extern bool kexec_file_dbg_print;
-#define kexec_dprintk(fmt, ...) \
- printk("%s" fmt, \
- kexec_file_dbg_print ? KERN_INFO : KERN_DEBUG, \
- ##__VA_ARGS__)
+#define kexec_dprintk(fmt, arg...) \
+ do { if (kexec_file_dbg_print) pr_info(fmt, ##arg); } while (0)
#else /* !CONFIG_KEXEC_CORE */
struct pt_regs;
_
Patches currently in -mm which might be from bhe(a)redhat.com are
The quilt patch titled
Subject: mm: fix race between __split_huge_pmd_locked() and GUP-fast
has been removed from the -mm tree. Its filename was
mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Ryan Roberts <ryan.roberts(a)arm.com>
Subject: mm: fix race between __split_huge_pmd_locked() and GUP-fast
Date: Wed, 1 May 2024 15:33:10 +0100
__split_huge_pmd_locked() can be called for a present THP, devmap or
(non-present) migration entry. It calls pmdp_invalidate() unconditionally
on the pmdp and only determines if it is present or not based on the
returned old pmd. This is a problem for the migration entry case because
pmd_mkinvalid(), called by pmdp_invalidate() must only be called for a
present pmd.
On arm64 at least, pmd_mkinvalid() will mark the pmd such that any future
call to pmd_present() will return true. And therefore any lockless
pgtable walker could see the migration entry pmd in this state and start
interpretting the fields as if it were present, leading to BadThings (TM).
GUP-fast appears to be one such lockless pgtable walker.
x86 does not suffer the above problem, but instead pmd_mkinvalid() will
corrupt the offset field of the swap entry within the swap pte. See link
below for discussion of that problem.
Fix all of this by only calling pmdp_invalidate() for a present pmd. And
for good measure let's add a warning to all implementations of
pmdp_invalidate[_ad](). I've manually reviewed all other
pmdp_invalidate[_ad]() call sites and believe all others to be conformant.
This is a theoretical bug found during code review. I don't have any test
case to trigger it in practice.
Link: https://lkml.kernel.org/r/20240501143310.1381675-1-ryan.roberts@arm.com
Link: https://lore.kernel.org/all/0dd7827a-6334-439a-8fd0-43c98e6af22b@arm.com/
Fixes: 84c3fc4e9c56 ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Ryan Roberts <ryan.roberts(a)arm.com>
Reviewed-by: Zi Yan <ziy(a)nvidia.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual(a)arm.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Andreas Larsson <andreas(a)gaisler.com>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar(a)kernel.org>
Cc: Borislav Petkov (AMD) <bp(a)alien8.de>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Christian Borntraeger <borntraeger(a)linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy(a)csgroup.eu>
Cc: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: "David S. Miller" <davem(a)davemloft.net>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Mark Rutland <mark.rutland(a)arm.com>
Cc: Naveen N. Rao <naveen.n.rao(a)linux.ibm.com>
Cc: Nicholas Piggin <npiggin(a)gmail.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Sven Schnelle <svens(a)linux.ibm.com>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Will Deacon <will(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
Documentation/mm/arch_pgtable_helpers.rst | 6 +-
arch/powerpc/mm/book3s64/pgtable.c | 1
arch/s390/include/asm/pgtable.h | 4 +
arch/sparc/mm/tlb.c | 1
arch/x86/mm/pgtable.c | 2
mm/huge_memory.c | 49 ++++++++++----------
mm/pgtable-generic.c | 2
7 files changed, 39 insertions(+), 26 deletions(-)
--- a/arch/powerpc/mm/book3s64/pgtable.c~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/arch/powerpc/mm/book3s64/pgtable.c
@@ -170,6 +170,7 @@ pmd_t pmdp_invalidate(struct vm_area_str
{
unsigned long old_pmd;
+ VM_WARN_ON_ONCE(!pmd_present(*pmdp));
old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID);
flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
return __pmd(old_pmd);
--- a/arch/s390/include/asm/pgtable.h~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/arch/s390/include/asm/pgtable.h
@@ -1769,8 +1769,10 @@ static inline pmd_t pmdp_huge_clear_flus
static inline pmd_t pmdp_invalidate(struct vm_area_struct *vma,
unsigned long addr, pmd_t *pmdp)
{
- pmd_t pmd = __pmd(pmd_val(*pmdp) | _SEGMENT_ENTRY_INVALID);
+ pmd_t pmd;
+ VM_WARN_ON_ONCE(!pmd_present(*pmdp));
+ pmd = __pmd(pmd_val(*pmdp) | _SEGMENT_ENTRY_INVALID);
return pmdp_xchg_direct(vma->vm_mm, addr, pmdp, pmd);
}
--- a/arch/sparc/mm/tlb.c~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/arch/sparc/mm/tlb.c
@@ -249,6 +249,7 @@ pmd_t pmdp_invalidate(struct vm_area_str
{
pmd_t old, entry;
+ VM_WARN_ON_ONCE(!pmd_present(*pmdp));
entry = __pmd(pmd_val(*pmdp) & ~_PAGE_VALID);
old = pmdp_establish(vma, address, pmdp, entry);
flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
--- a/arch/x86/mm/pgtable.c~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/arch/x86/mm/pgtable.c
@@ -631,6 +631,8 @@ int pmdp_clear_flush_young(struct vm_are
pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address,
pmd_t *pmdp)
{
+ VM_WARN_ON_ONCE(!pmd_present(*pmdp));
+
/*
* No flush is necessary. Once an invalid PTE is established, the PTE's
* access and dirty bits cannot be updated.
--- a/Documentation/mm/arch_pgtable_helpers.rst~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/Documentation/mm/arch_pgtable_helpers.rst
@@ -140,7 +140,8 @@ PMD Page Table Helpers
+---------------------------+--------------------------------------------------+
| pmd_swp_clear_soft_dirty | Clears a soft dirty swapped PMD |
+---------------------------+--------------------------------------------------+
-| pmd_mkinvalid | Invalidates a mapped PMD [1] |
+| pmd_mkinvalid | Invalidates a present PMD; do not call for |
+| | non-present PMD [1] |
+---------------------------+--------------------------------------------------+
| pmd_set_huge | Creates a PMD huge mapping |
+---------------------------+--------------------------------------------------+
@@ -196,7 +197,8 @@ PUD Page Table Helpers
+---------------------------+--------------------------------------------------+
| pud_mkdevmap | Creates a ZONE_DEVICE mapped PUD |
+---------------------------+--------------------------------------------------+
-| pud_mkinvalid | Invalidates a mapped PUD [1] |
+| pud_mkinvalid | Invalidates a present PUD; do not call for |
+| | non-present PUD [1] |
+---------------------------+--------------------------------------------------+
| pud_set_huge | Creates a PUD huge mapping |
+---------------------------+--------------------------------------------------+
--- a/mm/huge_memory.c~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/mm/huge_memory.c
@@ -2430,32 +2430,11 @@ static void __split_huge_pmd_locked(stru
return __split_huge_zero_page_pmd(vma, haddr, pmd);
}
- /*
- * Up to this point the pmd is present and huge and userland has the
- * whole access to the hugepage during the split (which happens in
- * place). If we overwrite the pmd with the not-huge version pointing
- * to the pte here (which of course we could if all CPUs were bug
- * free), userland could trigger a small page size TLB miss on the
- * small sized TLB while the hugepage TLB entry is still established in
- * the huge TLB. Some CPU doesn't like that.
- * See http://support.amd.com/TechDocs/41322_10h_Rev_Gd.pdf, Erratum
- * 383 on page 105. Intel should be safe but is also warns that it's
- * only safe if the permission and cache attributes of the two entries
- * loaded in the two TLB is identical (which should be the case here).
- * But it is generally safer to never allow small and huge TLB entries
- * for the same virtual address to be loaded simultaneously. So instead
- * of doing "pmd_populate(); flush_pmd_tlb_range();" we first mark the
- * current pmd notpresent (atomically because here the pmd_trans_huge
- * must remain set at all times on the pmd until the split is complete
- * for this pmd), then we flush the SMP TLB and finally we write the
- * non-huge version of the pmd entry with pmd_populate.
- */
- old_pmd = pmdp_invalidate(vma, haddr, pmd);
-
- pmd_migration = is_pmd_migration_entry(old_pmd);
+ pmd_migration = is_pmd_migration_entry(*pmd);
if (unlikely(pmd_migration)) {
swp_entry_t entry;
+ old_pmd = *pmd;
entry = pmd_to_swp_entry(old_pmd);
page = pfn_swap_entry_to_page(entry);
write = is_writable_migration_entry(entry);
@@ -2466,6 +2445,30 @@ static void __split_huge_pmd_locked(stru
soft_dirty = pmd_swp_soft_dirty(old_pmd);
uffd_wp = pmd_swp_uffd_wp(old_pmd);
} else {
+ /*
+ * Up to this point the pmd is present and huge and userland has
+ * the whole access to the hugepage during the split (which
+ * happens in place). If we overwrite the pmd with the not-huge
+ * version pointing to the pte here (which of course we could if
+ * all CPUs were bug free), userland could trigger a small page
+ * size TLB miss on the small sized TLB while the hugepage TLB
+ * entry is still established in the huge TLB. Some CPU doesn't
+ * like that. See
+ * http://support.amd.com/TechDocs/41322_10h_Rev_Gd.pdf, Erratum
+ * 383 on page 105. Intel should be safe but is also warns that
+ * it's only safe if the permission and cache attributes of the
+ * two entries loaded in the two TLB is identical (which should
+ * be the case here). But it is generally safer to never allow
+ * small and huge TLB entries for the same virtual address to be
+ * loaded simultaneously. So instead of doing "pmd_populate();
+ * flush_pmd_tlb_range();" we first mark the current pmd
+ * notpresent (atomically because here the pmd_trans_huge must
+ * remain set at all times on the pmd until the split is
+ * complete for this pmd), then we flush the SMP TLB and finally
+ * we write the non-huge version of the pmd entry with
+ * pmd_populate.
+ */
+ old_pmd = pmdp_invalidate(vma, haddr, pmd);
page = pmd_page(old_pmd);
folio = page_folio(page);
if (pmd_dirty(old_pmd)) {
--- a/mm/pgtable-generic.c~mm-fix-race-between-__split_huge_pmd_locked-and-gup-fast
+++ a/mm/pgtable-generic.c
@@ -198,6 +198,7 @@ pgtable_t pgtable_trans_huge_withdraw(st
pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
pmd_t *pmdp)
{
+ VM_WARN_ON_ONCE(!pmd_present(*pmdp));
pmd_t old = pmdp_establish(vma, address, pmdp, pmd_mkinvalid(*pmdp));
flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
return old;
@@ -208,6 +209,7 @@ pmd_t pmdp_invalidate(struct vm_area_str
pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address,
pmd_t *pmdp)
{
+ VM_WARN_ON_ONCE(!pmd_present(*pmdp));
return pmdp_invalidate(vma, address, pmdp);
}
#endif
_
Patches currently in -mm which might be from ryan.roberts(a)arm.com are