From b24bacd67ffddd9192c4745500fd6f73dbfe565e Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 24 Mar 2021 20:22:42 +0100 Subject: s390/vdso: fix tod_steering_delta type The s390 specific vdso function __arch_get_hw_counter() is supposed to consider tod clock steering. If a tod clock steering event happens and the tod clock is set to a new value __arch_get_hw_counter() will not return the real tod clock value but slowly drift it from the old delta until the returned value finally matches the real tod clock value again. Unfortunately the type of tod_steering_delta unsigned while it is supposed to be signed. It depends on if tod_steering_delta is negative or positive in which direction the vdso code drifts the clock value. Worst case is now that instead of drifting the clock slowly it will jump into the opposite direction by a factor of two. Fix this by simply making tod_steering_delta signed. Fixes: 4bff8cb54502 ("s390: convert to GENERIC_VDSO") Cc: # 5.10 Signed-off-by: Heiko Carstens --- arch/s390/include/asm/vdso/data.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390/include') diff --git a/arch/s390/include/asm/vdso/data.h b/arch/s390/include/asm/vdso/data.h index 7b3cdb4a5f48..73ee89142666 100644 --- a/arch/s390/include/asm/vdso/data.h +++ b/arch/s390/include/asm/vdso/data.h @@ -6,7 +6,7 @@ #include struct arch_vdso_data { - __u64 tod_steering_delta; + __s64 tod_steering_delta; __u64 tod_steering_end; }; -- cgit v1.2.3 From 08edb9683e47f5183aed9aa3f926292b54c278c1 Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Wed, 31 Mar 2021 11:44:50 +0200 Subject: s390/unwind: add machine check handler stack Fixes: b61b1595124a ("s390: add stack for machine check handler") Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens --- arch/s390/include/asm/stacktrace.h | 1 + arch/s390/kernel/dumpstack.c | 12 +++++++++++- 2 files changed, 12 insertions(+), 1 deletion(-) (limited to 'arch/s390/include') diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h index ee056f4a4fa3..2b543163d90a 100644 --- a/arch/s390/include/asm/stacktrace.h +++ b/arch/s390/include/asm/stacktrace.h @@ -12,6 +12,7 @@ enum stack_type { STACK_TYPE_IRQ, STACK_TYPE_NODAT, STACK_TYPE_RESTART, + STACK_TYPE_MCCK, }; struct stack_info { diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c index 0dc4b258b98d..db1bc00229ca 100644 --- a/arch/s390/kernel/dumpstack.c +++ b/arch/s390/kernel/dumpstack.c @@ -79,6 +79,15 @@ static bool in_nodat_stack(unsigned long sp, struct stack_info *info) return in_stack(sp, info, STACK_TYPE_NODAT, top - THREAD_SIZE, top); } +static bool in_mcck_stack(unsigned long sp, struct stack_info *info) +{ + unsigned long frame_size, top; + + frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs); + top = S390_lowcore.mcck_stack + frame_size; + return in_stack(sp, info, STACK_TYPE_MCCK, top - THREAD_SIZE, top); +} + static bool in_restart_stack(unsigned long sp, struct stack_info *info) { unsigned long frame_size, top; @@ -108,7 +117,8 @@ int get_stack_info(unsigned long sp, struct task_struct *task, /* Check per-cpu stacks */ if (!in_irq_stack(sp, info) && !in_nodat_stack(sp, info) && - !in_restart_stack(sp, info)) + !in_restart_stack(sp, info) && + !in_mcck_stack(sp, info)) goto unknown; recursion_check: -- cgit v1.2.3