kernel.git/drivers/acpi/apei, branch linux-5.19.y

ACPI: APEI: do not add task_work to kernel thread to avoid memory leak

2022-10-24T07:58:07Z

[ Upstream commit 415fed694fe11395df56e05022d6e7cee1d39dd3 ] If an error is detected as a result of user-space process accessing a corrupt memory location, the CPU may take an abort. Then the platform firmware reports kernel via NMI like notifications, e.g. NOTIFY_SEA, NOTIFY_SOFTWARE_DELEGATED, etc. For NMI like notifications, commit 7f17b4a121d0 ("ACPI: APEI: Kick the memory_failure() queue for synchronous errors") keep track of whether memory_failure() work was queued, and make task_work pending to flush out the queue so that the work is processed before return to user-space. The code use init_mm to check whether the error occurs in user space: if (current->mm != &init_mm) The condition is always true, becase _nobody_ ever has "init_mm" as a real VM any more. In addition to abort, errors can also be signaled as asynchronous exceptions, such as interrupt and SError. In such case, the interrupted current process could be any kind of thread. When a kernel thread is interrupted, the work ghes_kick_task_work deferred to task_work will never be processed because entry_handler returns to call ret_to_kernel() instead of ret_to_user(). Consequently, the estatus_node alloced from ghes_estatus_pool in ghes_in_nmi_queue_one_entry() will not be freed. After around 200 allocations in our platform, the ghes_estatus_pool will run of memory and ghes_in_nmi_queue_one_entry() returns ENOMEM. As a result, the event failed to be processed. sdei: event 805 on CPU 113 failed with error: -2 Finally, a lot of unhandled events may cause platform firmware to exceed some threshold and reboot. The condition should generally just do if (current->mm) as described in active_mm.rst documentation. Then if an asynchronous error is detected when a kernel thread is running, (e.g. when detected by a background scrubber), do not add task_work to it as the original patch intends to do. Fixes: 7f17b4a121d0 ("ACPI: APEI: Kick the memory_failure() queue for synchronous errors") Signed-off-by: Shuai Xue Reviewed-by: Tony Luck Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: APEI: Fix _EINJ vs EFI_MEMORY_SP

2022-08-17T13:14:12Z

[ Upstream commit b13a3e5fd40b7d1b394c5ecbb5eb301a4c38e7b2 ] When a platform marks a memory range as "special purpose" it is not onlined as System RAM by default. However, it is still suitable for error injection. Add IORES_DESC_SOFT_RESERVED to einj_error_inject() as a permissible memory type in the sanity checking of the arguments to _EINJ. Fixes: 262b45ae3ab4 ("x86/efi: EFI soft reservation to E820 enumeration") Reviewed-by: Tony Luck Reported-by: Omar Avelar Signed-off-by: Dan Williams Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

ACPI: APEI: Better fix to avoid spamming the console with old error logs

2022-08-11T11:22:03Z

commit c3481b6b75b4797657838f44028fd28226ab48e0 upstream. The fix in commit 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT table data") does not work as intended on systems where the BIOS has a fixed size block of memory for the BERT table, relying on s/w to quit when it finds a record with estatus->block_status == 0. On these systems all errors are suppressed because the check: if (region_len < ACPI_BERT_PRINT_MAX_LEN) always fails. New scheme skips individual CPER records that are too large, and also limits the total number of records that will be printed to 5. Fixes: 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT table data") Cc: All applicable Signed-off-by: Tony Luck Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI, APEI, EINJ: Refuse to inject into the zero page

2022-04-22T14:52:27Z

Some validation tests dynamically inject errors into memory used by applications to check that the system can recover from a variety of poison consumption sceenarios. But sometimes the virtual address picked by these tests is mapped to the zero page. This causes additional unexpected machine checks as other processes that map the zero page also consume the poison. Disallow injection to the zero page. Signed-off-by: Tony Luck Signed-off-by: Rafael J. Wysocki

ACPI: APEI: Fix missing ERST record id

2022-04-13T18:29:24Z

Read a record is cleared by others, but the deleted record cache entry is still created by erst_get_record_id_next. When next enumerate the records, get the cached deleted record, then erst_read() return -ENOENT and try to get next record, loop back to first ID will return 0 in function __erst_record_id_cache_add_one and then set record_id as APEI_ERST_INVALID_RECORD_ID, finished this time read operation. It will result in read the records just in the cache hereafter. This patch cleared the deleted record cache, fix the issue that "./erst-inject -p" shows record counts not equal to "./erst-inject -n". A reproducer of the problem(retry many times): [root@localhost erst-inject]# ./erst-inject -c 0xaaaaa00011 [root@localhost erst-inject]# ./erst-inject -p rc: 273 rcd sig: CPER rcd id: 0xaaaaa00012 rc: 273 rcd sig: CPER rcd id: 0xaaaaa00013 rc: 273 rcd sig: CPER rcd id: 0xaaaaa00014 [root@localhost erst-inject]# ./erst-inject -i 0xaaaaa000006 [root@localhost erst-inject]# ./erst-inject -i 0xaaaaa000007 [root@localhost erst-inject]# ./erst-inject -i 0xaaaaa000008 [root@localhost erst-inject]# ./erst-inject -p rc: 273 rcd sig: CPER rcd id: 0xaaaaa00012 rc: 273 rcd sig: CPER rcd id: 0xaaaaa00013 rc: 273 rcd sig: CPER rcd id: 0xaaaaa00014 [root@localhost erst-inject]# ./erst-inject -n total error record count: 6 Signed-off-by: Liu Xinpeng Reviewed-by: Tony Luck Signed-off-by: Rafael J. Wysocki

ACPI, APEI: Use the correct variable for sizeof()

2022-03-22T17:52:21Z

While the original code is valid, it is not the obvious choice for the sizeof() call and in preparation to limit the scope of the list iterator variable the sizeof should be changed to the size of the variable being allocated. Signed-off-by: Jakob Koschel Signed-off-by: Rafael J. Wysocki

ACPI/APEI: Limit printable size of BERT table data

2022-03-09T18:40:13Z

Platforms with large BERT table data can trigger soft lockup errors while attempting to print the entire BERT table data to the console at boot: watchdog: BUG: soft lockup - CPU#160 stuck for 23s! [swapper/0:1] Observed on Ampere Altra systems with a single BERT record of ~250KB. The original bert driver appears to have assumed relatively small table data. Since it is impractical to reassemble large table data from interwoven console messages, and the table data is available in /sys/firmware/acpi/tables/data/BERT limit the size for tables printed to the console to 1024 (for no reason other than it seemed like a good place to kick off the discussion, would appreciate feedback from existing users in terms of what size would maintain their current usage model). Alternatively, we could make printing a CONFIG option, use the bert_disable boot arg (or something similar), or use a debug log level. However, all those solutions require extra steps or change the existing behavior for small table data. Limiting the size preserves existing behavior on existing platforms with small table data, and eliminates the soft lockups for platforms with large table data, while still making it available. Signed-off-by: Darren Hart Signed-off-by: Rafael J. Wysocki

ACPI: APEI: fix return value of __setup handlers

2022-03-08T18:43:39Z

__setup() handlers should return 1 to indicate that the boot option has been handled. Returning 0 causes a boot option to be listed in the Unknown kernel command line parameters and also added to init's arg list (if no '=' sign) or environment list (if of the form 'a=b'). Unknown kernel command line parameters "erst_disable bert_disable hest_disable BOOT_IMAGE=/boot/bzImage-517rc6", will be passed to user space. Run /sbin/init as init process with arguments: /sbin/init erst_disable bert_disable hest_disable with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc6 Fixes: a3e2acc5e37b ("ACPI / APEI: Add Boot Error Record Table (BERT) support") Fixes: a08f82d08053 ("ACPI, APEI, Error Record Serialization Table (ERST) support") Fixes: 9dc966641677 ("ACPI, APEI, HEST table parsing") Signed-off-by: Randy Dunlap Reported-by: Igor Zhbanov Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Reviewed-by: "Huang, Ying" Signed-off-by: Rafael J. Wysocki

ACPI: APEI: rename ghes_init() with an "acpi_" prefix

2022-03-03T19:25:23Z

ghes_init() sticks out in acpi_init() because it is the only functions without an "acpi_" prefix. Rename ghes_init with an "acpi_" prefix, then all looks fine. Signed-off-by: Shuai Xue Signed-off-by: Rafael J. Wysocki

ACPI: APEI: explicit init of HEST and GHES in apci_init()

2022-03-03T19:24:22Z

From commit e147133a42cb ("ACPI / APEI: Make hest.c manage the estatus memory pool") was merged, ghes_init() relies on acpi_hest_init() to manage the estatus memory pool. On the other hand, ghes_init() relies on sdei_init() to detect the SDEI version and (un)register events. The dependencies are as follows: ghes_init() => acpi_hest_init() => acpi_bus_init() => acpi_init() ghes_init() => sdei_init() HEST is not PCI-specific and initcall ordering is implicit and not well-defined within a level. Based on above, remove acpi_hest_init() from acpi_pci_root_init() and convert ghes_init() and sdei_init() from initcalls to explicit calls in the following order: acpi_hest_init() ghes_init() sdei_init() Signed-off-by: Shuai Xue Signed-off-by: Rafael J. Wysocki