[PATCH v0 05/12] x86/mce: Allow instrumentation during task work queueing

Borislav Petkov
2021-11-04T14:40:58Z

vmlinux.o: warning: objtool: do_machine_check()+0xdb1: call to queue_task_work() leaves .noinstr.text section

Signed-off-by: Borislav Petkov <bp@suse.de>
---
arch/x86/kernel/cpu/mce/core.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index c7181e8e2845..65a8be420aff 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1451,6 +1451,8 @@ noinstr void do_machine_check(struct pt_regs *regs)
if (worst != MCE_AR_SEVERITY && !kill_current_task)
goto out;

+ 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 +1481,9 @@ 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);
}
--
2.29.2