* Re: [PATCH v2] ACPI: APEI: Handle repeated SEA error storms
2026-05-27 8:27 [PATCH v2] ACPI: APEI: Handle repeated SEA error storms Junhao He
@ 2026-05-28 1:48 ` mawupeng
2026-07-02 12:50 ` hejunhao
2026-07-08 17:14 ` Luck, Tony
2 siblings, 0 replies; 6+ messages in thread
From: mawupeng @ 2026-05-28 1:48 UTC (permalink / raw)
To: hejunhao3, rafael, tony.luck, guohanjun, mchehab, xueshuai,
jarkko, yazen.ghannam, jane.chu, lenb, linmiaohe
Cc: mawupeng1, bp, linux-acpi, linux-arm-kernel, linux-kernel,
linux-edac, tanxiaofei, linuxarm, liuyonglong
On 周三 2026-5-27 16:27, Junhao He wrote:
> When hardware memory corruption occurs and a user process accesses the
> corrupted page, the CPU triggers a Synchronous External Abort (SEA).
> The kernel invokes do_sea() to handle the exception, which calls
> memory_failure() to handle the faulty page.
>
> Scenario 1: Memory Error Interrupt First, then SEA
> The page is already poisoned by the memory error interrupt path. The
> subsequent SEA handler sends a SIGBUS to the task, which accesses the
> poisoned page. This flow is correct.
>
> Scenario 2: SEA first, then memory error interrupt (problematic scenario)
> If a user task directly accesses corrupted memory through a PFNMAP-style
> mapping (e.g., devmem), the page may still be in the free-buddy state when
> SEA is handled. In this case, memory_failure() will poison the page without
> invoking kill_accessing_process(), and then takes the free-buddy recovery
> path.
>
> After the CPU returns to the task context, the task re-enters the SEA
> handler due to the same access. However, ghes_estatus_cached() suppresses
> all subsequent entries during the 10-second window, preventing
> ghes_do_proc() from being called. This suppression blocks the
> MF_ACTION_REQUIRED-based SIGBUS delivery, causing the kernel to fail to
> kill the task immediately. Consequently, the process keeps re-entering
> the SEA handler, leading to an SEA storm. Later, the memory error
> interrupt path also cannot kill the task, leaving the system stuck in
> this repeated loop.
>
> The following error logs are explained using the devmem process:
> NOTICE: SEA Handle
> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> [Hardware Error]: event severity: recoverable
> [Hardware Error]: section_type: ARM processor error
> [Hardware Error]: physical fault address: 0x0000001000093c00
> [T54990] Memory failure: 0x1000093: recovery action for free buddy page: Recovered
> [ T9955] EDAC MC0: 1 UE Multi-bit ECC on unknown memory
> (page:0x1000093 offset:0xc00 grain:1 - APEI location: ...)
> NOTICE: SEA Handle
> NOTICE: SEA Handle
> ...
> ... ---> SEA storm
> ...
> NOTICE: SEA Handle
> [ T9955] Memory failure: 0x1000093: already hardware poisoned
> ghes_print_estatus: 1 callbacks suppressed
> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> [Hardware Error]: event severity: recoverable
> [Hardware Error]: section_type: ARM processor error
> [Hardware Error]: physical fault address: 0x0000001000093c00
> [T54990] Memory failure: 0x1000093: already hardware poisoned
> [T54990] 0x1000093: Sending SIGBUS to devmem:54990 due to hardware memory corruption
>
> To resolve this, return an error when encountering the same SEA again.
> The subsequent SEA handler invocation uses arm64_notify_die() to send a
> SIGBUS signal to the task, which terminates the process and prevents it
> from re-entering the handler loop.
>
> Signed-off-by: Junhao He <hejunhao3@h-partners.com>
Reviewed-by: Wupeng Ma <mawupeng1@huawei.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] ACPI: APEI: Handle repeated SEA error storms
2026-05-27 8:27 [PATCH v2] ACPI: APEI: Handle repeated SEA error storms Junhao He
2026-05-28 1:48 ` mawupeng
@ 2026-07-02 12:50 ` hejunhao
2026-07-02 13:01 ` Rafael J. Wysocki (Intel)
2026-07-08 1:42 ` Shuai Xue
2026-07-08 17:14 ` Luck, Tony
2 siblings, 2 replies; 6+ messages in thread
From: hejunhao @ 2026-07-02 12:50 UTC (permalink / raw)
To: rafael, tony.luck, guohanjun, mchehab, xueshuai, jarkko,
yazen.ghannam, jane.chu, lenb, linmiaohe
Cc: Junhao He, bp, linux-acpi, linux-arm-kernel, linux-kernel,
linux-edac, tanxiaofei, liuyonglong, mawupeng1
Gentle ping for this one, and it's ready.
Best regards,
On 2026/5/27 16:27, Junhao He wrote:
> When hardware memory corruption occurs and a user process accesses the
> corrupted page, the CPU triggers a Synchronous External Abort (SEA).
> The kernel invokes do_sea() to handle the exception, which calls
> memory_failure() to handle the faulty page.
>
> Scenario 1: Memory Error Interrupt First, then SEA
> The page is already poisoned by the memory error interrupt path. The
> subsequent SEA handler sends a SIGBUS to the task, which accesses the
> poisoned page. This flow is correct.
>
> Scenario 2: SEA first, then memory error interrupt (problematic scenario)
> If a user task directly accesses corrupted memory through a PFNMAP-style
> mapping (e.g., devmem), the page may still be in the free-buddy state when
> SEA is handled. In this case, memory_failure() will poison the page without
> invoking kill_accessing_process(), and then takes the free-buddy recovery
> path.
>
> After the CPU returns to the task context, the task re-enters the SEA
> handler due to the same access. However, ghes_estatus_cached() suppresses
> all subsequent entries during the 10-second window, preventing
> ghes_do_proc() from being called. This suppression blocks the
> MF_ACTION_REQUIRED-based SIGBUS delivery, causing the kernel to fail to
> kill the task immediately. Consequently, the process keeps re-entering
> the SEA handler, leading to an SEA storm. Later, the memory error
> interrupt path also cannot kill the task, leaving the system stuck in
> this repeated loop.
>
> The following error logs are explained using the devmem process:
> NOTICE: SEA Handle
> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> [Hardware Error]: event severity: recoverable
> [Hardware Error]: section_type: ARM processor error
> [Hardware Error]: physical fault address: 0x0000001000093c00
> [T54990] Memory failure: 0x1000093: recovery action for free buddy page: Recovered
> [ T9955] EDAC MC0: 1 UE Multi-bit ECC on unknown memory
> (page:0x1000093 offset:0xc00 grain:1 - APEI location: ...)
> NOTICE: SEA Handle
> NOTICE: SEA Handle
> ...
> ... ---> SEA storm
> ...
> NOTICE: SEA Handle
> [ T9955] Memory failure: 0x1000093: already hardware poisoned
> ghes_print_estatus: 1 callbacks suppressed
> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> [Hardware Error]: event severity: recoverable
> [Hardware Error]: section_type: ARM processor error
> [Hardware Error]: physical fault address: 0x0000001000093c00
> [T54990] Memory failure: 0x1000093: already hardware poisoned
> [T54990] 0x1000093: Sending SIGBUS to devmem:54990 due to hardware memory corruption
>
> To resolve this, return an error when encountering the same SEA again.
> The subsequent SEA handler invocation uses arm64_notify_die() to send a
> SIGBUS signal to the task, which terminates the process and prevents it
> from re-entering the handler loop.
>
> Signed-off-by: Junhao He <hejunhao3@h-partners.com>
> ---
> drivers/acpi/apei/ghes.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> Changes in V2:
> 1. update the commit message per suggestion from Xueshuai
> 2. Add a check to only return failure on the ghes_notify_sea() path,
> avoiding impact on other NMI-type GHES handlers.
> Link to V1 - https://lore.kernel.org/all/20251030071321.2763224-1-hejunhao3@h-partners.com/
>
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 3236a3ce79d6..787664740150 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -1383,8 +1383,16 @@ static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
> ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
>
> /* This error has been reported before, don't process it again. */
> - if (ghes_estatus_cached(estatus))
> + if (ghes_estatus_cached(estatus)) {
> + /*
> + * Return failure on duplicate SEA entries so that the
> + * subsequent SEA handler invocation sends a SIGBUS signal to
> + * the task to prevent it from re-entering the handler loop.
> + */
> + if (is_hest_sync_notify(ghes))
> + rc = -ECANCELED;
> goto no_work;
> + }
>
> llist_add(&estatus_node->llnode, &ghes_estatus_llist);
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] ACPI: APEI: Handle repeated SEA error storms
2026-07-02 12:50 ` hejunhao
@ 2026-07-02 13:01 ` Rafael J. Wysocki (Intel)
2026-07-08 1:42 ` Shuai Xue
1 sibling, 0 replies; 6+ messages in thread
From: Rafael J. Wysocki (Intel) @ 2026-07-02 13:01 UTC (permalink / raw)
To: hejunhao
Cc: rafael, tony.luck, guohanjun, mchehab, xueshuai, jarkko,
yazen.ghannam, jane.chu, lenb, linmiaohe, bp, linux-acpi,
linux-arm-kernel, linux-kernel, linux-edac, tanxiaofei,
liuyonglong, mawupeng1
On Thu, Jul 2, 2026 at 2:50 PM hejunhao <hejunhao3@h-partners.com> wrote:
>
> Gentle ping for this one, and it's ready.
So it requires at least one ACK from a person listed as APEI reviewers
in MAINTAINERS.
> On 2026/5/27 16:27, Junhao He wrote:
> > When hardware memory corruption occurs and a user process accesses the
> > corrupted page, the CPU triggers a Synchronous External Abort (SEA).
> > The kernel invokes do_sea() to handle the exception, which calls
> > memory_failure() to handle the faulty page.
> >
> > Scenario 1: Memory Error Interrupt First, then SEA
> > The page is already poisoned by the memory error interrupt path. The
> > subsequent SEA handler sends a SIGBUS to the task, which accesses the
> > poisoned page. This flow is correct.
> >
> > Scenario 2: SEA first, then memory error interrupt (problematic scenario)
> > If a user task directly accesses corrupted memory through a PFNMAP-style
> > mapping (e.g., devmem), the page may still be in the free-buddy state when
> > SEA is handled. In this case, memory_failure() will poison the page without
> > invoking kill_accessing_process(), and then takes the free-buddy recovery
> > path.
> >
> > After the CPU returns to the task context, the task re-enters the SEA
> > handler due to the same access. However, ghes_estatus_cached() suppresses
> > all subsequent entries during the 10-second window, preventing
> > ghes_do_proc() from being called. This suppression blocks the
> > MF_ACTION_REQUIRED-based SIGBUS delivery, causing the kernel to fail to
> > kill the task immediately. Consequently, the process keeps re-entering
> > the SEA handler, leading to an SEA storm. Later, the memory error
> > interrupt path also cannot kill the task, leaving the system stuck in
> > this repeated loop.
> >
> > The following error logs are explained using the devmem process:
> > NOTICE: SEA Handle
> > [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> > [Hardware Error]: event severity: recoverable
> > [Hardware Error]: section_type: ARM processor error
> > [Hardware Error]: physical fault address: 0x0000001000093c00
> > [T54990] Memory failure: 0x1000093: recovery action for free buddy page: Recovered
> > [ T9955] EDAC MC0: 1 UE Multi-bit ECC on unknown memory
> > (page:0x1000093 offset:0xc00 grain:1 - APEI location: ...)
> > NOTICE: SEA Handle
> > NOTICE: SEA Handle
> > ...
> > ... ---> SEA storm
> > ...
> > NOTICE: SEA Handle
> > [ T9955] Memory failure: 0x1000093: already hardware poisoned
> > ghes_print_estatus: 1 callbacks suppressed
> > [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> > [Hardware Error]: event severity: recoverable
> > [Hardware Error]: section_type: ARM processor error
> > [Hardware Error]: physical fault address: 0x0000001000093c00
> > [T54990] Memory failure: 0x1000093: already hardware poisoned
> > [T54990] 0x1000093: Sending SIGBUS to devmem:54990 due to hardware memory corruption
> >
> > To resolve this, return an error when encountering the same SEA again.
> > The subsequent SEA handler invocation uses arm64_notify_die() to send a
> > SIGBUS signal to the task, which terminates the process and prevents it
> > from re-entering the handler loop.
> >
> > Signed-off-by: Junhao He <hejunhao3@h-partners.com>
> > ---
> > drivers/acpi/apei/ghes.c | 10 +++++++++-
> > 1 file changed, 9 insertions(+), 1 deletion(-)
> >
> > Changes in V2:
> > 1. update the commit message per suggestion from Xueshuai
> > 2. Add a check to only return failure on the ghes_notify_sea() path,
> > avoiding impact on other NMI-type GHES handlers.
> > Link to V1 - https://lore.kernel.org/all/20251030071321.2763224-1-hejunhao3@h-partners.com/
> >
> > diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> > index 3236a3ce79d6..787664740150 100644
> > --- a/drivers/acpi/apei/ghes.c
> > +++ b/drivers/acpi/apei/ghes.c
> > @@ -1383,8 +1383,16 @@ static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
> > ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
> >
> > /* This error has been reported before, don't process it again. */
> > - if (ghes_estatus_cached(estatus))
> > + if (ghes_estatus_cached(estatus)) {
> > + /*
> > + * Return failure on duplicate SEA entries so that the
> > + * subsequent SEA handler invocation sends a SIGBUS signal to
> > + * the task to prevent it from re-entering the handler loop.
> > + */
> > + if (is_hest_sync_notify(ghes))
> > + rc = -ECANCELED;
> > goto no_work;
> > + }
> >
> > llist_add(&estatus_node->llnode, &ghes_estatus_llist);
> >
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] ACPI: APEI: Handle repeated SEA error storms
2026-07-02 12:50 ` hejunhao
2026-07-02 13:01 ` Rafael J. Wysocki (Intel)
@ 2026-07-08 1:42 ` Shuai Xue
1 sibling, 0 replies; 6+ messages in thread
From: Shuai Xue @ 2026-07-08 1:42 UTC (permalink / raw)
To: hejunhao, rafael, tony.luck, guohanjun, mchehab, jarkko,
yazen.ghannam, jane.chu, lenb, linmiaohe, Borislav Petkov
Cc: linux-acpi, linux-arm-kernel, linux-kernel, linux-edac,
tanxiaofei, liuyonglong, mawupeng1
+ Tony, and BP,
On 7/2/26 8:50 PM, hejunhao wrote:
> Gentle ping for this one, and it's ready.
>
> Best regards,
>
>
> On 2026/5/27 16:27, Junhao He wrote:
>> When hardware memory corruption occurs and a user process accesses the
>> corrupted page, the CPU triggers a Synchronous External Abort (SEA).
>> The kernel invokes do_sea() to handle the exception, which calls
>> memory_failure() to handle the faulty page.
>>
>> Scenario 1: Memory Error Interrupt First, then SEA
>> The page is already poisoned by the memory error interrupt path. The
>> subsequent SEA handler sends a SIGBUS to the task, which accesses the
>> poisoned page. This flow is correct.
>>
>> Scenario 2: SEA first, then memory error interrupt (problematic scenario)
>> If a user task directly accesses corrupted memory through a PFNMAP-style
>> mapping (e.g., devmem), the page may still be in the free-buddy state when
>> SEA is handled. In this case, memory_failure() will poison the page without
>> invoking kill_accessing_process(), and then takes the free-buddy recovery
>> path.
>>
>> After the CPU returns to the task context, the task re-enters the SEA
>> handler due to the same access. However, ghes_estatus_cached() suppresses
>> all subsequent entries during the 10-second window, preventing
>> ghes_do_proc() from being called. This suppression blocks the
>> MF_ACTION_REQUIRED-based SIGBUS delivery, causing the kernel to fail to
>> kill the task immediately. Consequently, the process keeps re-entering
>> the SEA handler, leading to an SEA storm. Later, the memory error
>> interrupt path also cannot kill the task, leaving the system stuck in
>> this repeated loop.
>>
>> The following error logs are explained using the devmem process:
>> NOTICE: SEA Handle
>> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
>> [Hardware Error]: event severity: recoverable
>> [Hardware Error]: section_type: ARM processor error
>> [Hardware Error]: physical fault address: 0x0000001000093c00
>> [T54990] Memory failure: 0x1000093: recovery action for free buddy page: Recovered
>> [ T9955] EDAC MC0: 1 UE Multi-bit ECC on unknown memory
>> (page:0x1000093 offset:0xc00 grain:1 - APEI location: ...)
>> NOTICE: SEA Handle
>> NOTICE: SEA Handle
>> ...
>> ... ---> SEA storm
>> ...
>> NOTICE: SEA Handle
>> [ T9955] Memory failure: 0x1000093: already hardware poisoned
>> ghes_print_estatus: 1 callbacks suppressed
>> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
>> [Hardware Error]: event severity: recoverable
>> [Hardware Error]: section_type: ARM processor error
>> [Hardware Error]: physical fault address: 0x0000001000093c00
>> [T54990] Memory failure: 0x1000093: already hardware poisoned
>> [T54990] 0x1000093: Sending SIGBUS to devmem:54990 due to hardware memory corruption
>>
>> To resolve this, return an error when encountering the same SEA again.
>> The subsequent SEA handler invocation uses arm64_notify_die() to send a
>> SIGBUS signal to the task, which terminates the process and prevents it
>> from re-entering the handler loop.
>>
>> Signed-off-by: Junhao He <hejunhao3@h-partners.com>
>> ---
>> drivers/acpi/apei/ghes.c | 10 +++++++++-
>> 1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> Changes in V2:
>> 1. update the commit message per suggestion from Xueshuai
>> 2. Add a check to only return failure on the ghes_notify_sea() path,
>> avoiding impact on other NMI-type GHES handlers.
>> Link to V1 - https://lore.kernel.org/all/20251030071321.2763224-1-hejunhao3@h-partners.com/
>>
>> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
>> index 3236a3ce79d6..787664740150 100644
>> --- a/drivers/acpi/apei/ghes.c
>> +++ b/drivers/acpi/apei/ghes.c
>> @@ -1383,8 +1383,16 @@ static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
>> ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
>>
>> /* This error has been reported before, don't process it again. */
>> - if (ghes_estatus_cached(estatus))
>> + if (ghes_estatus_cached(estatus)) {
>> + /*
>> + * Return failure on duplicate SEA entries so that the
>> + * subsequent SEA handler invocation sends a SIGBUS signal to
>> + * the task to prevent it from re-entering the handler loop.
>> + */
>> + if (is_hest_sync_notify(ghes))
>> + rc = -ECANCELED;
>> goto no_work;
>> + }
>>
>> llist_add(&estatus_node->llnode, &ghes_estatus_llist);
>>
Hello Tony, BP,
Could you please take a look at this patch?
Since `ghes_in_nmi_queue_one_entry()` is a common path for both ARM64
and x86, an Ack from the x86 side would be appreciated.
For ARM part, look good to me.
Reviewed-by: Shuai Xue <xueshuai@linux.alibaba.com>
Thanks.
Shuai
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] ACPI: APEI: Handle repeated SEA error storms
2026-05-27 8:27 [PATCH v2] ACPI: APEI: Handle repeated SEA error storms Junhao He
2026-05-28 1:48 ` mawupeng
2026-07-02 12:50 ` hejunhao
@ 2026-07-08 17:14 ` Luck, Tony
2 siblings, 0 replies; 6+ messages in thread
From: Luck, Tony @ 2026-07-08 17:14 UTC (permalink / raw)
To: Junhao He
Cc: rafael, guohanjun, mchehab, xueshuai, jarkko, yazen.ghannam,
jane.chu, lenb, linmiaohe, bp, linux-acpi, linux-arm-kernel,
linux-kernel, linux-edac, tanxiaofei, linuxarm, liuyonglong,
mawupeng1
On Wed, May 27, 2026 at 04:27:07PM +0800, Junhao He wrote:
> When hardware memory corruption occurs and a user process accesses the
> corrupted page, the CPU triggers a Synchronous External Abort (SEA).
> The kernel invokes do_sea() to handle the exception, which calls
> memory_failure() to handle the faulty page.
>
> Scenario 1: Memory Error Interrupt First, then SEA
> The page is already poisoned by the memory error interrupt path. The
> subsequent SEA handler sends a SIGBUS to the task, which accesses the
> poisoned page. This flow is correct.
>
> Scenario 2: SEA first, then memory error interrupt (problematic scenario)
> If a user task directly accesses corrupted memory through a PFNMAP-style
> mapping (e.g., devmem), the page may still be in the free-buddy state when
> SEA is handled. In this case, memory_failure() will poison the page without
> invoking kill_accessing_process(), and then takes the free-buddy recovery
> path.
>
> After the CPU returns to the task context, the task re-enters the SEA
> handler due to the same access. However, ghes_estatus_cached() suppresses
> all subsequent entries during the 10-second window, preventing
> ghes_do_proc() from being called. This suppression blocks the
> MF_ACTION_REQUIRED-based SIGBUS delivery, causing the kernel to fail to
> kill the task immediately. Consequently, the process keeps re-entering
> the SEA handler, leading to an SEA storm. Later, the memory error
> interrupt path also cannot kill the task, leaving the system stuck in
> this repeated loop.
>
> The following error logs are explained using the devmem process:
> NOTICE: SEA Handle
> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> [Hardware Error]: event severity: recoverable
> [Hardware Error]: section_type: ARM processor error
> [Hardware Error]: physical fault address: 0x0000001000093c00
> [T54990] Memory failure: 0x1000093: recovery action for free buddy page: Recovered
> [ T9955] EDAC MC0: 1 UE Multi-bit ECC on unknown memory
> (page:0x1000093 offset:0xc00 grain:1 - APEI location: ...)
> NOTICE: SEA Handle
> NOTICE: SEA Handle
> ...
> ... ---> SEA storm
> ...
> NOTICE: SEA Handle
> [ T9955] Memory failure: 0x1000093: already hardware poisoned
> ghes_print_estatus: 1 callbacks suppressed
> [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
> [Hardware Error]: event severity: recoverable
> [Hardware Error]: section_type: ARM processor error
> [Hardware Error]: physical fault address: 0x0000001000093c00
> [T54990] Memory failure: 0x1000093: already hardware poisoned
> [T54990] 0x1000093: Sending SIGBUS to devmem:54990 due to hardware memory corruption
>
> To resolve this, return an error when encountering the same SEA again.
> The subsequent SEA handler invocation uses arm64_notify_die() to send a
> SIGBUS signal to the task, which terminates the process and prevents it
> from re-entering the handler loop.
>
> Signed-off-by: Junhao He <hejunhao3@h-partners.com>
> ---
> drivers/acpi/apei/ghes.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> Changes in V2:
> 1. update the commit message per suggestion from Xueshuai
> 2. Add a check to only return failure on the ghes_notify_sea() path,
> avoiding impact on other NMI-type GHES handlers.
> Link to V1 - https://lore.kernel.org/all/20251030071321.2763224-1-hejunhao3@h-partners.com/
>
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 3236a3ce79d6..787664740150 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -1383,8 +1383,16 @@ static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
ghes_in_nmi_queue_one_entry() is called from two places:
__ghes_sdei_callback()
I think, but I'm not sure, that you are addressing call from here. By
returning -ECANCELLED this code skips the irq_work_queue() call and
returns -ENOENT (instead of zero).
ghes_in_nmi_spool_from_list()
Effect here is more complex. Depends on whether there are multiple
ghes entries on the rcu_list. If there was just one, and you return
-ECANCELLED, then irq_work_queue() is skipped. But if there are multiple
entries on the list and at least one of them gets a zero return from
ghes_in_nmi_queue_one_entry() then irq_work_queue() is called.
So which of these callers is the one that needs this fix? And is the
other called OK with getting -ECANCELLED error?
> ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx);
>
> /* This error has been reported before, don't process it again. */
> - if (ghes_estatus_cached(estatus))
> + if (ghes_estatus_cached(estatus)) {
> + /*
> + * Return failure on duplicate SEA entries so that the
> + * subsequent SEA handler invocation sends a SIGBUS signal to
> + * the task to prevent it from re-entering the handler loop.
> + */
> + if (is_hest_sync_notify(ghes))
> + rc = -ECANCELED;
> goto no_work;
> + }
>
> llist_add(&estatus_node->llnode, &ghes_estatus_llist);
>
> --
> 2.33.0
>
-Tony
^ permalink raw reply [flat|nested] 6+ messages in thread