The following commit has been merged into the ras/core branch of tip: Commit-ID: 4fbce464db81a42f9a57ee242d6150ec7f996415 Gitweb: https://git.kernel.org/tip/4fbce464db81a42f9a57ee242d6150ec7f996415 Author: Borislav Petkov <bp@xxxxxxx> AuthorDate: Wed, 13 Oct 2021 09:07:19 +02:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Mon, 13 Dec 2021 14:12:35 +01:00 x86/mce: Allow instrumentation during task work queueing Fixes vmlinux.o: warning: objtool: do_machine_check()+0xdb1: call to queue_task_work() leaves .noinstr.text section Signed-off-by: Borislav Petkov <bp@xxxxxxx> Link: https://lore.kernel.org/r/20211208111343.8130-6-bp@xxxxxxxxx --- arch/x86/kernel/cpu/mce/core.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index c11fc8d..d788ccc 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1459,6 +1459,14 @@ noinstr void do_machine_check(struct pt_regs *regs) if (worst != MCE_AR_SEVERITY && !kill_current_task) goto out; + /* + * Enable instrumentation around the external facilities like + * task_work_add() (via queue_task_work()), fixup_exception() etc. + * For now, that is. Fixing this properly would need a lot more involved + * reorganization. + */ + instrumentation_begin(); + /* Fault was in user mode and we need to take some action */ if ((m.cs & 3) == 3) { /* If this triggers there is no way to recover. Die hard. */ @@ -1487,6 +1495,9 @@ noinstr void do_machine_check(struct pt_regs *regs) if (m.kflags & MCE_IN_KERNEL_COPYIN) queue_task_work(&m, msg, kill_me_never); } + + instrumentation_end(); + out: mce_wrmsrl(MSR_IA32_MCG_STATUS, 0); }