Messages in this thread Patch in this message | | | Date | Sun, 24 May 2020 15:08:03 -0000 | From | Thomas Gleixner <> | Subject | [GIT pull] x86/urgent for v5.7-rc7 |
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Linus,
please pull the latest x86/urgent branch from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-2020-05-24
up to: 187b96db5ca7: x86/unwind/orc: Fix unwind_get_return_address_ptr() for inactive tasks
Two fixes for x86:
- Unbreak stack dumps for inactive tasks by interpreting the special first frame left by __switch_to_asm() correctly. The recent change not to skip the first frame so ORC and frame unwinder behave in the same way caused all entries to be unreliable, i.e. prepended with '?'.
- Use cpumask_available() instead of an implicit NULL check of a cpumask_var_t in mmio trace to prevent a Clang build warning
Thanks,
tglx
------------------> Josh Poimboeuf (1): x86/unwind/orc: Fix unwind_get_return_address_ptr() for inactive tasks
Nathan Chancellor (1): x86/mmiotrace: Use cpumask_available() for cpumask_var_t variables
arch/x86/kernel/unwind_orc.c | 7 +++++++ arch/x86/mm/mmio-mod.c | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c index fa79e4227d3d..7f969b2d240f 100644 --- a/arch/x86/kernel/unwind_orc.c +++ b/arch/x86/kernel/unwind_orc.c @@ -320,12 +320,19 @@ EXPORT_SYMBOL_GPL(unwind_get_return_address); unsigned long *unwind_get_return_address_ptr(struct unwind_state *state) { + struct task_struct *task = state->task; + if (unwind_done(state)) return NULL; if (state->regs) return &state->regs->ip; + if (task != current && state->sp == task->thread.sp) { + struct inactive_task_frame *frame = (void *)task->thread.sp; + return &frame->ret_addr; + } + if (state->sp) return (unsigned long *)state->sp - 1; diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c index 109325d77b3e..43fd19b3f118 100644 --- a/arch/x86/mm/mmio-mod.c +++ b/arch/x86/mm/mmio-mod.c @@ -372,7 +372,7 @@ static void enter_uniprocessor(void) int cpu; int err; - if (downed_cpus == NULL && + if (!cpumask_available(downed_cpus) && !alloc_cpumask_var(&downed_cpus, GFP_KERNEL)) { pr_notice("Failed to allocate mask\n"); goto out; @@ -402,7 +402,7 @@ static void leave_uniprocessor(void) int cpu; int err; - if (downed_cpus == NULL || cpumask_weight(downed_cpus) == 0) + if (!cpumask_available(downed_cpus) || cpumask_weight(downed_cpus) == 0) return; pr_notice("Re-enabling CPUs...\n"); for_each_cpu(cpu, downed_cpus) {
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