From f2bde2aeb1aea77b56d151b293a03cd5b1a19d07 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Wed, 13 Oct 2021 09:07:19 +0200 Subject: [PATCH] x86/mce: Allow instrumentation during task work queueing [ Upstream commit 4fbce464db81a42f9a57ee242d6150ec7f996415 ] Fixes vmlinux.o: warning: objtool: do_machine_check()+0xdb1: call to queue_task_work() leaves .noinstr.text section Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20211208111343.8130-6-bp@alien8.de Signed-off-by: Sasha Levin --- 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 193204a..c8d1210 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1454,6 +1454,14 @@ 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. */ @@ -1479,6 +1487,9 @@ noinstr void do_machine_check(struct pt_regs *regs) if (m.kflags & MCE_IN_KERNEL_COPYIN) queue_task_work(&m, msg, kill_current_task); } + + instrumentation_end(); + out: mce_wrmsrl(MSR_IA32_MCG_STATUS, 0); } -- 2.7.4