Re: [PATCH] powerpc/traps: fix recoverability of machine check handling on book3s/32

Hello,

Le 11/09/2020 à 11:15, Michal Suchánek a écrit :

Hello,

does this logic apply to "Unrecoverable System Reset" as well?

I don't know, I don't think I have any way the generate a System Reset on my board to check it.

Christophe

Thanks

Michal

On Tue, Jan 22, 2019 at 02:11:24PM +0000, Christophe Leroy wrote:

quoted

Looks like book3s/32 doesn't set RI on machine check, so
checking RI before calling die() will always be fatal
allthought this is not an issue in most cases.

Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt")
Fixes: daf00ae71dad ("powerpc/traps: restore recoverability of machine_check interrupts")
Signed-off-by: Christophe Leroy <redacted>
Cc: stable@vger.kernel.org
---
  arch/powerpc/kernel/traps.c | 8 ++++----
  1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 64936b60d521..c740f8bfccc9 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c

@@ -763,15 +763,15 @@ void machine_check_exception(struct pt_regs *regs)
  	if (check_io_access(regs))
  		goto bail;
  
-	/* Must die if the interrupt is not recoverable */
-	if (!(regs->msr & MSR_RI))
-		nmi_panic(regs, "Unrecoverable Machine check");
-
  	if (!nested)
  		nmi_exit();
  
  	die("Machine check", regs, SIGBUS);
  
+	/* Must die if the interrupt is not recoverable */
+	if (!(regs->msr & MSR_RI))
+		nmi_panic(regs, "Unrecoverable Machine check");
+
  	return;
  
  bail:

-- 
2.13.3