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| author | Vasily Gorbik <gor@linux.ibm.com> | 2019-12-11 17:27:31 +0100 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2019-12-18 23:29:26 +0100 |
| commit | eef06cbf670aaa2ccb56c9a7b84042acd657aa5d (patch) | |
| tree | d7ec3302b9c80e67babb6e27dddc79b28b1508c5 /arch | |
| parent | c23587c92f6e3260fe3b82bb75b38aa2553b9468 (diff) | |
| download | linux-eef06cbf670aaa2ccb56c9a7b84042acd657aa5d.tar.gz | |
s390/unwind: stop gracefully at user mode pt_regs in irq stack
Consider reaching user mode pt_regs at the bottom of irq stack graceful unwinder termination. This is the case when irq/mcck/ext interrupt arrives while in user mode. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/kernel/unwind_bc.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/arch/s390/kernel/unwind_bc.c b/arch/s390/kernel/unwind_bc.c index da2d4d4c5b0e..707fd99f6734 100644 --- a/arch/s390/kernel/unwind_bc.c +++ b/arch/s390/kernel/unwind_bc.c @@ -36,10 +36,17 @@ static bool update_stack_info(struct unwind_state *state, unsigned long sp) return true; } -static inline bool is_task_pt_regs(struct unwind_state *state, - struct pt_regs *regs) +static inline bool is_final_pt_regs(struct unwind_state *state, + struct pt_regs *regs) { - return task_pt_regs(state->task) == regs; + /* user mode or kernel thread pt_regs at the bottom of task stack */ + if (task_pt_regs(state->task) == regs) + return true; + + /* user mode pt_regs at the bottom of irq stack */ + return state->stack_info.type == STACK_TYPE_IRQ && + state->stack_info.end - sizeof(struct pt_regs) == (unsigned long)regs && + READ_ONCE_NOCHECK(regs->psw.mask) & PSW_MASK_PSTATE; } bool unwind_next_frame(struct unwind_state *state) @@ -80,7 +87,7 @@ bool unwind_next_frame(struct unwind_state *state) if (!on_stack(info, sp, sizeof(struct pt_regs))) goto out_err; regs = (struct pt_regs *) sp; - if (is_task_pt_regs(state, regs)) + if (is_final_pt_regs(state, regs)) goto out_stop; ip = READ_ONCE_NOCHECK(regs->psw.addr); sp = READ_ONCE_NOCHECK(regs->gprs[15]); |