7d444f5099
EINJ driver today only allows injection request to go through for two
kinds of IORESOURCE_MEM: IORES_DESC_PERSISTENT_MEMORY and
IORES_DESC_SOFT_RESERVED. This check prevents user of EINJ to test
memory corrupted in many interesting areas:
- Legacy persistent memory
- Memory claimed to be used by ACPI tables or NV storage
- Kernel crash memory and others
There is need to test how kernel behaves when something consumes memory
errors in these memory regions. For example, if certain ACPI table is
corrupted, does kernel crash gracefully to prevent "silent data
corruption". For another example, legacy persistent memory, when managed
by Device DAX, does support recovering from Machine Check Exception
raised by memory failure, hence worth to be tested.
However, attempt to inject memory error via EINJ to legacy persistent
memory or ACPI owned memory fails with -EINVAL.
Allow EINJ to inject at address except it is MMIO. Leave it to the BIOS
or firmware to decide what is a legitimate injection target.
In addition to the test done in [1], on a machine having the following
iomem resources:
...
01000000-08ffffff : Crash kernel
768f0098-768f00a7 : APEI EINJ
...
768f4000-77323fff : ACPI Non-volatile Storage
77324000-777fefff : ACPI Tables
777ff000-777fffff : System RAM
77800000-7fffffff : Reserved
80000000-8fffffff : PCI MMCONFIG 0000 [bus 00-ff]
90040000-957fffff : PCI Bus 0000:00
...
300000000-3ffffffff : Persistent Memory (legacy)
...
I commented __einj_error_inject during the test and just tested when
injecting a memory error at each start address shown above:
- 0x80000000 and 0x90040000 both failed with EINVAL
- request passed through for all other addresses
Link: https://lore.kernel.org/linux-acpi/20250825223348.3780279-1-jiaqiyan@google.com [1]
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://patch.msgid.link/20250910044531.264043-1-jiaqiyan@google.com
[ rjw: Adding a link tag for the [1] reference ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
||
|---|---|---|
| .. | ||
| Kconfig | ||
| Makefile | ||
| apei-base.c | ||
| apei-internal.h | ||
| bert.c | ||
| einj-core.c | ||
| einj-cxl.c | ||
| erst-dbg.c | ||
| erst.c | ||
| ghes.c | ||
| hest.c | ||