| Message ID | 790e46767a5f10ae991969b064682c8c82f96bc3.1610519852.git.christophe.leroy@csgroup.eu |
|---|---|
| State | New |
| Headers | show |
| Series | [for,5.10] powerpc/32s: Fix RTAS machine check with VMAP stack | expand |
diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index a0dda2a1f2df..d66da35f2e8d 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -262,10 +262,19 @@ __secondary_hold_acknowledge: MachineCheck: EXCEPTION_PROLOG_0 #ifdef CONFIG_PPC_CHRP +#ifdef CONFIG_VMAP_STACK + mr r11, r1 + mfspr r1, SPRN_SPRG_THREAD + lwz r1, RTAS_SP(r1) + cmpwi cr1, r1, 0 + bne cr1, 7f + mr r1, r11 +#else mfspr r11, SPRN_SPRG_THREAD lwz r11, RTAS_SP(r11) cmpwi cr1, r11, 0 bne cr1, 7f +#endif #endif /* CONFIG_PPC_CHRP */ EXCEPTION_PROLOG_1 for_rtas=1 7: EXCEPTION_PROLOG_2
This is backport for 5.10 (cherry picked from commit 98bf2d3f4970179c702ef64db658e0553bc6ef3a) When we have VMAP stack, exception prolog 1 sets r1, not r11. When it is not an RTAS machine check, don't trash r1 because it is needed by prolog 1. Fixes: da7bb43ab9da ("powerpc/32: Fix vmap stack - Properly set r1 before activating MMU") Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Squash in fixup for RTAS machine check from Christophe] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/bc77d61d1c18940e456a2dee464f1e2eda65a3f0.1608621048.git.christophe.leroy@csgroup.eu --- arch/powerpc/kernel/head_book3s_32.S | 9 +++++++++ 1 file changed, 9 insertions(+)