From 5cd474e57368f0957c343bb21e309cf82826b1ef Mon Sep 17 00:00:00 2001 From: D Scott Phillips Date: Mon, 26 Jun 2023 17:29:39 -0700 Subject: arm64: sdei: abort running SDEI handlers during crash Interrupts are blocked in SDEI context, per the SDEI spec: "The client interrupts cannot preempt the event handler." If we crashed in the SDEI handler-running context (as with ACPI's AGDI) then we need to clean up the SDEI state before proceeding to the crash kernel so that the crash kernel can have working interrupts. Track the active SDEI handler per-cpu so that we can COMPLETE_AND_RESUME the handler, discarding the interrupted context. Fixes: f5df26961853 ("arm64: kernel: Add arch-specific SDEI entry code and CPU masking") Signed-off-by: D Scott Phillips Cc: stable@vger.kernel.org Reviewed-by: James Morse Tested-by: Mihai Carabas Link: https://lore.kernel.org/r/20230627002939.2758-1-scott@os.amperecomputing.com Signed-off-by: Will Deacon --- arch/arm64/kernel/smp.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/arm64/kernel/smp.c') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index edd63894d61e..960b98b43506 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -1044,10 +1044,8 @@ void crash_smp_send_stop(void) * If this cpu is the only one alive at this point in time, online or * not, there are no stop messages to be sent around, so just back out. */ - if (num_other_online_cpus() == 0) { - sdei_mask_local_cpu(); - return; - } + if (num_other_online_cpus() == 0) + goto skip_ipi; cpumask_copy(&mask, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &mask); @@ -1066,7 +1064,9 @@ void crash_smp_send_stop(void) pr_warn("SMP: failed to stop secondary CPUs %*pbl\n", cpumask_pr_args(&mask)); +skip_ipi: sdei_mask_local_cpu(); + sdei_handler_abort(); } bool smp_crash_stop_failed(void) -- cgit v1.2.3