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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2020-09-07 16:42:09 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-09-15 15:13:33 +0300 |
| commit | c118c7303ad528be8ff2aea8cd1ee15452c763f0 (patch) | |
| tree | 6d4c98677a61815048a13eedbe9784c1aa4160b5 /arch/powerpc/kernel/head_32.S | |
| parent | 7fdf966bed155b214f4f1f9b67825a40b2e9b998 (diff) | |
| download | linux-c118c7303ad528be8ff2aea8cd1ee15452c763f0.tar.xz | |
powerpc/32: Fix vmap stack - Do not activate MMU before reading task struct
We need r1 to be properly set before activating MMU, so
reading task_struct->stack must be done with MMU off.
This means we need an additional register to play with MSR
bits while r11 now points to the stack. For that, move r10
back to CR (As is already done for hash MMU) and use r10.
We still don't have r1 correct yet when we activate MMU.
It is done in following patch.
Fixes: 028474876f47 ("powerpc/32: prepare for CONFIG_VMAP_STACK")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a027d447022a006c9c4958ac734128e577a3c5c1.1599486108.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/kernel/head_32.S')
| -rw-r--r-- | arch/powerpc/kernel/head_32.S | 6 |
1 files changed, 0 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S index 5624db0e09a1..b0e184f795c0 100644 --- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S @@ -274,14 +274,8 @@ __secondary_hold_acknowledge: DO_KVM 0x200 MachineCheck: EXCEPTION_PROLOG_0 -#ifdef CONFIG_VMAP_STACK - li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */ - mtmsr r11 - isync -#endif #ifdef CONFIG_PPC_CHRP mfspr r11, SPRN_SPRG_THREAD - tovirt_vmstack r11, r11 lwz r11, RTAS_SP(r11) cmpwi cr1, r11, 0 bne cr1, 7f |