Per definition of the daifflags, Serrors can occur during any interrupt context, that includes NMI contexts. Trying to nmi_enter in an nmi context will crash.
Skip nmi_enter/nmi_exit when serror occurred during an NMI. Suggested-by: James Morse <james.mo...@arm.com> Signed-off-by: Julien Thierry <julien.thie...@arm.com> Cc: Catalin Marinas <catalin.mari...@arm.com> Cc: Will Deacon <will.dea...@arm.com> Cc: Mark Rutland <mark.rutl...@arm.com> Cc: Dave Martin <dave.mar...@arm.com> Cc: James Morse <james.mo...@arm.com> --- arch/arm64/kernel/traps.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 039e9ff..4955ec6 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -713,13 +713,17 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr) asmlinkage void do_serror(struct pt_regs *regs, unsigned int esr) { - nmi_enter(); + const bool was_in_nmi = in_nmi(); + + if (!was_in_nmi) + nmi_enter(); /* non-RAS errors are not containable */ if (!arm64_is_ras_serror(esr) || arm64_is_fatal_ras_serror(regs, esr)) arm64_serror_panic(regs, esr); - nmi_exit(); + if (!was_in_nmi) + nmi_exit(); } void __pte_error(const char *file, int line, unsigned long val) -- 1.9.1