On Mon, Oct 28, 2024 at 04:11:40PM +0800, Shuai Xue wrote: > Synchronous error was detected as a result of user-space process accessing > a 2-bit uncorrected error. The CPU will take a synchronous error exception > such as Synchronous External Abort (SEA) on Arm64. The kernel will queue a > memory_failure() work which poisons the related page, unmaps the page, and > then sends a SIGBUS to the process, so that a system wide panic can be > avoided. > > However, no memory_failure() work will be queued when abnormal synchronous > errors occur. These errors can include situations such as invalid PA, > unexpected severity, no memory failure config support, invalid GUID > section, etc. In such case, the user-space process will trigger SEA again. > This loop can potentially exceed the platform firmware threshold or even > trigger a kernel hard lockup, leading to a system reboot. > > Fix it by performing a force kill if no memory_failure() work is queued > for synchronous errors. > > Signed-off-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx> > Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > --- > drivers/acpi/apei/ghes.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c > index ada93cfde9ba..f2ee28c44d7a 100644 > --- a/drivers/acpi/apei/ghes.c > +++ b/drivers/acpi/apei/ghes.c > @@ -801,6 +801,16 @@ static bool ghes_do_proc(struct ghes *ghes, > } > } > > + /* > + * If no memory failure work is queued for abnormal synchronous > + * errors, do a force kill. > + */ > + if (sync && !queued) { > + pr_err("%s:%d: hardware memory corruption (SIGBUS)\n", > + current->comm, task_pid_nr(current)); I think it would help to include the GHES_PFX to indicate where this message is coming from. The pr_fmt() macro could also be introduced instead. Also, you may want to include the HW_ERR prefix. Not all kernel messages related to hardware errors have this prefix today. But maybe that should be changed so there is more consistent messaging. Thanks, Yazen