Re: [PATCH] ACPI: APEI: Handle repeated SEA error interrupts storm scenarios
From: Shuai Xue
Date: Tue Mar 24 2026 - 22:12:39 EST
Hi, junhao
On 3/24/26 6:04 PM, hejunhao wrote:
Hi shuai xue,
On 2026/3/3 22:42, Shuai Xue wrote:
Hi, junhao,
On 2/27/26 8:12 PM, hejunhao wrote:
On 2025/11/4 9:32, Shuai Xue wrote:
在 2025/11/4 00:19, Rafael J. Wysocki 写道:
On Thu, Oct 30, 2025 at 8:13 AM Junhao He <hejunhao3@xxxxxxxxxxxxxx> wrote:
The do_sea() function defaults to using firmware-first mode, if supported.
It invoke acpi/apei/ghes ghes_notify_sea() to report and handling the SEA
error, The GHES uses a buffer to cache the most recent 4 kinds of SEA
errors. If the same kind SEA error continues to occur, GHES will skip to
reporting this SEA error and will not add it to the "ghes_estatus_llist"
list until the cache times out after 10 seconds, at which point the SEA
error will be reprocessed.
The GHES invoke ghes_proc_in_irq() to handle the SEA error, which
ultimately executes memory_failure() to process the page with hardware
memory corruption. If the same SEA error appears multiple times
consecutively, it indicates that the previous handling was incomplete or
unable to resolve the fault. In such cases, it is more appropriate to
return a failure when encountering the same error again, and then proceed
to arm64_do_kernel_sea for further processing.
There is no such function in the arm64 tree. If apei_claim_sea() returns
Sorry for the mistake in the commit message. The function arm64_do_kernel_sea() should
be arm64_notify_die().
an error, the actual fallback path in do_sea() is arm64_notify_die(),
which sends SIGBUS?
If apei_claim_sea() returns an error, arm64_notify_die() will call arm64_force_sig_fault(inf->sig /* SIGBUS */, , , ),
followed by force_sig_fault(SIGBUS, , ) to force the process to receive the SIGBUS signal.
So the process is expected to killed by SIGBUS?
When hardware memory corruption occurs, a memory error interrupt is
triggered. If the kernel accesses this erroneous data, it will trigger
the SEA error exception handler. All such handlers will call
memory_failure() to handle the faulty page.
If a memory error interrupt occurs first, followed by an SEA error
interrupt, the faulty page is first marked as poisoned by the memory error
interrupt process, and then the SEA error interrupt handling process will
send a SIGBUS signal to the process accessing the poisoned page.
However, if the SEA interrupt is reported first, the following exceptional
scenario occurs:
When a user process directly requests and accesses a page with hardware
memory corruption via mmap (such as with devmem), the page containing this
address may still be in a free buddy state in the kernel. At this point,
the page is marked as "poisoned" during the SEA claim memory_failure().
However, since the process does not request the page through the kernel's
MMU, the kernel cannot send SIGBUS signal to the processes. And the memory
error interrupt handling process not support send SIGBUS signal. As a
result, these processes continues to access the faulty page, causing
repeated entries into the SEA exception handler. At this time, it lead to
an SEA error interrupt storm.
In such case, the user process which accessing the poisoned page will be killed
by memory_fauilre?
// memory_failure():
if (TestSetPageHWPoison(p)) {
res = -EHWPOISON;
if (flags & MF_ACTION_REQUIRED)
res = kill_accessing_process(current, pfn, flags);
if (flags & MF_COUNT_INCREASED)
put_page(p);
action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
goto unlock_mutex;
}
I think this problem has already been fixed by commit 2e6053fea379 ("mm/memory-failure:
fix infinite UCE for VM_PFNMAP pfn").
The root cause is that walk_page_range() skips VM_PFNMAP vmas by default when
no .test_walk callback is set, so kill_accessing_process() returns 0 for a
devmem-style mapping (remap_pfn_range, VM_PFNMAP), making the caller believe
the UCE was handled properly while the process was never actually killed.
Did you try the lastest kernel version?
I retested this issue on the kernel v7.0.0-rc4 with the following debug patch and was still able to reproduce it.
@@ -1365,8 +1365,11 @@ 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)) {
+ pr_info("This error has been reported before, don't process it again.\n");
goto no_work;
+ }
the test log Only some debug logs are retained here.
[2026/3/24 14:51:58.199] [root@localhost ~]# taskset -c 40 busybox devmem 0x1351811824 32 0
[2026/3/24 14:51:58.369] [root@localhost ~]# taskset -c 40 busybox devmem 0x1351811824 32
[2026/3/24 14:51:58.458] [ 130.558038][ C40] {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
[2026/3/24 14:51:58.459] [ 130.572517][ C40] {1}[Hardware Error]: event severity: recoverable
[2026/3/24 14:51:58.459] [ 130.578861][ C40] {1}[Hardware Error]: Error 0, type: recoverable
[2026/3/24 14:51:58.459] [ 130.585203][ C40] {1}[Hardware Error]: section_type: ARM processor error
[2026/3/24 14:51:58.459] [ 130.592238][ C40] {1}[Hardware Error]: MIDR: 0x0000000000000000
[2026/3/24 14:51:58.459] [ 130.598492][ C40] {1}[Hardware Error]: Multiprocessor Affinity Register (MPIDR): 0x0000000081010400
[2026/3/24 14:51:58.459] [ 130.607871][ C40] {1}[Hardware Error]: error affinity level: 0
[2026/3/24 14:51:58.459] [ 130.614038][ C40] {1}[Hardware Error]: running state: 0x1
[2026/3/24 14:51:58.459] [ 130.619770][ C40] {1}[Hardware Error]: Power State Coordination Interface state: 0
[2026/3/24 14:51:58.459] [ 130.627673][ C40] {1}[Hardware Error]: Error info structure 0:
[2026/3/24 14:51:58.459] [ 130.633839][ C40] {1}[Hardware Error]: num errors: 1
[2026/3/24 14:51:58.459] [ 130.639137][ C40] {1}[Hardware Error]: error_type: 0, cache error
[2026/3/24 14:51:58.459] [ 130.645652][ C40] {1}[Hardware Error]: error_info: 0x0000000020400014
[2026/3/24 14:51:58.459] [ 130.652514][ C40] {1}[Hardware Error]: cache level: 1
[2026/3/24 14:51:58.551] [ 130.658073][ C40] {1}[Hardware Error]: the error has not been corrected
[2026/3/24 14:51:58.551] [ 130.665194][ C40] {1}[Hardware Error]: physical fault address: 0x0000001351811800
[2026/3/24 14:51:58.551] [ 130.673097][ C40] {1}[Hardware Error]: Vendor specific error info has 48 bytes:
[2026/3/24 14:51:58.551] [ 130.680744][ C40] {1}[Hardware Error]: 00000000: 00000000 00000000 00000000 00000000 ................
[2026/3/24 14:51:58.551] [ 130.690471][ C40] {1}[Hardware Error]: 00000010: 00000000 00000000 00000000 00000000 ................
[2026/3/24 14:51:58.552] [ 130.700198][ C40] {1}[Hardware Error]: 00000020: 00000000 00000000 00000000 00000000 ................
[2026/3/24 14:51:58.552] [ 130.710083][ T9767] Memory failure: 0x1351811: recovery action for free buddy page: Recovered
[2026/3/24 14:51:58.638] [ 130.790952][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:51:58.903] [ 131.046994][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:51:58.991] [ 131.132360][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:51:59.969] [ 132.071431][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:00.860] [ 133.010255][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:01.927] [ 134.034746][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:02.906] [ 135.058973][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:03.971] [ 136.083213][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:04.860] [ 137.021956][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:06.018] [ 138.131460][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:06.905] [ 139.070280][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:07.886] [ 140.009147][ C40] This error has been reported before, don't process it again.
[2026/3/24 14:52:08.596] [ 140.777368][ C40] {2}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
[2026/3/24 14:52:08.683] [ 140.791921][ C40] {2}[Hardware Error]: event severity: recoverable
[2026/3/24 14:52:08.683] [ 140.798263][ C40] {2}[Hardware Error]: Error 0, type: recoverable
[2026/3/24 14:52:08.683] [ 140.804606][ C40] {2}[Hardware Error]: section_type: ARM processor error
[2026/3/24 14:52:08.683] [ 140.811641][ C40] {2}[Hardware Error]: MIDR: 0x0000000000000000
[2026/3/24 14:52:08.684] [ 140.817895][ C40] {2}[Hardware Error]: Multiprocessor Affinity Register (MPIDR): 0x0000000081010400
[2026/3/24 14:52:08.684] [ 140.827274][ C40] {2}[Hardware Error]: error affinity level: 0
[2026/3/24 14:52:08.684] [ 140.833440][ C40] {2}[Hardware Error]: running state: 0x1
[2026/3/24 14:52:08.684] [ 140.839173][ C40] {2}[Hardware Error]: Power State Coordination Interface state: 0
[2026/3/24 14:52:08.684] [ 140.847076][ C40] {2}[Hardware Error]: Error info structure 0:
[2026/3/24 14:52:08.684] [ 140.853241][ C40] {2}[Hardware Error]: num errors: 1
[2026/3/24 14:52:08.684] [ 140.858540][ C40] {2}[Hardware Error]: error_type: 0, cache error
[2026/3/24 14:52:08.684] [ 140.865055][ C40] {2}[Hardware Error]: error_info: 0x0000000020400014
[2026/3/24 14:52:08.684] [ 140.871917][ C40] {2}[Hardware Error]: cache level: 1
[2026/3/24 14:52:08.684] [ 140.877475][ C40] {2}[Hardware Error]: the error has not been corrected
[2026/3/24 14:52:08.764] [ 140.884596][ C40] {2}[Hardware Error]: physical fault address: 0x0000001351811800
[2026/3/24 14:52:08.764] [ 140.892499][ C40] {2}[Hardware Error]: Vendor specific error info has 48 bytes:
[2026/3/24 14:52:08.766] [ 140.900145][ C40] {2}[Hardware Error]: 00000000: 00000000 00000000 00000000 00000000 ................
[2026/3/24 14:52:08.767] [ 140.909872][ C40] {2}[Hardware Error]: 00000010: 00000000 00000000 00000000 00000000 ................
[2026/3/24 14:52:08.767] [ 140.919598][ C40] {2}[Hardware Error]: 00000020: 00000000 00000000 00000000 00000000 ................
[2026/3/24 14:52:08.768] [ 140.929346][ T9767] Memory failure: 0x1351811: already hardware poisoned
[2026/3/24 14:52:08.768] [ 140.936072][ T9767] Memory failure: 0x1351811: Sending SIGBUS to busybox:9767 due to hardware memory corruption
Did you cut off some logs here?
The error log also indicates that the SIGBUS is delivered as expected.
Apply the patch:
@@ -1365,8 +1365,11 @@ 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)) {
+ pr_info("This error has been reported before, don't process it again.\n");
+ rc = -ECANCELED;
goto no_work;
+ }
[2026/3/24 16:45:40.084] [root@localhost ~]# taskset -c 40 busybox devmem 0x1351811824 32 0
[2026/3/24 16:45:40.272] [root@localhost ~]# taskset -c 40 busybox devmem 0x1351811824 32
[2026/3/24 16:45:40.362] [ 112.279324][ C40] {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 9
[2026/3/24 16:45:40.362] [ 112.293797][ C40] {1}[Hardware Error]: event severity: recoverable
[2026/3/24 16:45:40.362] [ 112.300139][ C40] {1}[Hardware Error]: Error 0, type: recoverable
[2026/3/24 16:45:40.363] [ 112.306481][ C40] {1}[Hardware Error]: section_type: ARM processor error
[2026/3/24 16:45:40.363] [ 112.313516][ C40] {1}[Hardware Error]: MIDR: 0x0000000000000000
[2026/3/24 16:45:40.363] [ 112.319771][ C40] {1}[Hardware Error]: Multiprocessor Affinity Register (MPIDR): 0x0000000081010400
[2026/3/24 16:45:40.363] [ 112.329151][ C40] {1}[Hardware Error]: error affinity level: 0
[2026/3/24 16:45:40.363] [ 112.335317][ C40] {1}[Hardware Error]: running state: 0x1
[2026/3/24 16:45:40.363] [ 112.341049][ C40] {1}[Hardware Error]: Power State Coordination Interface state: 0
[2026/3/24 16:45:40.363] [ 112.348953][ C40] {1}[Hardware Error]: Error info structure 0:
[2026/3/24 16:45:40.363] [ 112.355119][ C40] {1}[Hardware Error]: num errors: 1
[2026/3/24 16:45:40.363] [ 112.360418][ C40] {1}[Hardware Error]: error_type: 0, cache error
[2026/3/24 16:45:40.363] [ 112.366932][ C40] {1}[Hardware Error]: error_info: 0x0000000020400014
[2026/3/24 16:45:40.363] [ 112.373795][ C40] {1}[Hardware Error]: cache level: 1
[2026/3/24 16:45:40.453] [ 112.379354][ C40] {1}[Hardware Error]: the error has not been corrected
[2026/3/24 16:45:40.453] [ 112.386475][ C40] {1}[Hardware Error]: physical fault address: 0x0000001351811800
[2026/3/24 16:45:40.453] [ 112.394378][ C40] {1}[Hardware Error]: Vendor specific error info has 48 bytes:
[2026/3/24 16:45:40.453] [ 112.402027][ C40] {1}[Hardware Error]: 00000000: 00000000 00000000 00000000 00000000 ................
[2026/3/24 16:45:40.453] [ 112.411754][ C40] {1}[Hardware Error]: 00000010: 00000000 00000000 00000000 00000000 ................
[2026/3/24 16:45:40.453] [ 112.421480][ C40] {1}[Hardware Error]: 00000020: 00000000 00000000 00000000 00000000 ................
[2026/3/24 16:45:40.453] [ 112.431639][ T9769] Memory failure: 0x1351811: recovery action for free buddy page: Recovered
[2026/3/24 16:45:40.531] [ 112.512520][ C40] This error has been reported before, don't process it again.
[2026/3/24 16:45:40.757] Bus error (core dumped)
Thanks.
Shuai