This is a note to let you know that I've just added the patch titled
powerpc/85xx: Fix math emulation exception
to the 6.5-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-85xx-fix-math-emulation-exception.patch
and it can be found in the queue-6.5 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b680e0976d31c9948cf3a7f1c42f0785fb97e744
Author: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Date: Mon Sep 25 17:55:51 2023 +0200
powerpc/85xx: Fix math emulation exception
[ Upstream commit 8e8a12ecbc86700b5e1a3596ce2b3c43dafad336 ]
Booting mpc85xx_defconfig kernel on QEMU leads to:
Bad trap at PC: fe9bab0, SR: 2d000, vector=800
awk[82]: unhandled trap (5) at 0 nip fe9bab0 lr fe9e01c code 5 in libc-2.27.so[fe5a000+17a000]
awk[82]: code: 3aa00000 3a800010 4bffe03c 9421fff0 7ca62b78 38a00000 93c10008 83c10008
awk[82]: code: 38210010 4bffdec8 9421ffc0 7c0802a6 <fc00048e> d8010008 4815190d 93810030
Trace/breakpoint trap
WARNING: no useful console
This is because allthough CONFIG_MATH_EMULATION is selected,
Exception 800 calls unknown_exception().
Call emulation_assist_interrupt() instead.
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://msgid.link/066caa6d9480365da9b8ed83692d7101e10ac5f8.1695657339.git.christophe.leroy@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/kernel/head_85xx.S b/arch/powerpc/kernel/head_85xx.S
index fdbee1093e2ba..f9634111e82ed 100644
--- a/arch/powerpc/kernel/head_85xx.S
+++ b/arch/powerpc/kernel/head_85xx.S
@@ -396,7 +396,7 @@ interrupt_base:
#ifdef CONFIG_PPC_FPU
FP_UNAVAILABLE_EXCEPTION
#else
- EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, unknown_exception)
+ EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, emulation_assist_interrupt)
#endif
/* System Call Interrupt */
