From: Christophe Leroy christophe.leroy@csgroup.eu
[ Upstream commit db972a3787d12b1ce9ba7a31ec376d8a79e04c47 ]
low_sleep_handler() can't restore the context from standard stack because the stack can hardly be accessed with MMU OFF.
Store everything in a global storage area instead of storing a pointer to the stack in that global storage area.
To avoid a complete churn of the function, still use r1 as the pointer to the storage area during restore.
Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK") Reported-by: Giuseppe Sacco giuseppe@sguazz.it Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Tested-by: Giuseppe Sacco giuseppe@sguazz.it Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/e3e0d8042a3ba75cb4a9546c19c408b5b5b28994.160740493... Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/platforms/Kconfig.cputype | 2 +- arch/powerpc/platforms/powermac/sleep.S | 132 +++++++++++------------- 2 files changed, 60 insertions(+), 74 deletions(-)
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index c194c4ae8bc7d..32a9c4c09b989 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -36,7 +36,7 @@ config PPC_BOOK3S_6xx select PPC_HAVE_PMU_SUPPORT select PPC_HAVE_KUEP select PPC_HAVE_KUAP - select HAVE_ARCH_VMAP_STACK if !ADB_PMU + select HAVE_ARCH_VMAP_STACK
config PPC_85xx bool "Freescale 85xx" diff --git a/arch/powerpc/platforms/powermac/sleep.S b/arch/powerpc/platforms/powermac/sleep.S index 7e0f8ba6e54a5..d497a60003d2d 100644 --- a/arch/powerpc/platforms/powermac/sleep.S +++ b/arch/powerpc/platforms/powermac/sleep.S @@ -44,7 +44,8 @@ #define SL_TB 0xa0 #define SL_R2 0xa8 #define SL_CR 0xac -#define SL_R12 0xb0 /* r12 to r31 */ +#define SL_LR 0xb0 +#define SL_R12 0xb4 /* r12 to r31 */ #define SL_SIZE (SL_R12 + 80)
.section .text @@ -63,105 +64,107 @@ _GLOBAL(low_sleep_handler) blr #else mflr r0 - stw r0,4(r1) - stwu r1,-SL_SIZE(r1) + lis r11,sleep_storage@ha + addi r11,r11,sleep_storage@l + stw r0,SL_LR(r11) mfcr r0 - stw r0,SL_CR(r1) - stw r2,SL_R2(r1) - stmw r12,SL_R12(r1) + stw r0,SL_CR(r11) + stw r1,SL_SP(r11) + stw r2,SL_R2(r11) + stmw r12,SL_R12(r11)
/* Save MSR & SDR1 */ mfmsr r4 - stw r4,SL_MSR(r1) + stw r4,SL_MSR(r11) mfsdr1 r4 - stw r4,SL_SDR1(r1) + stw r4,SL_SDR1(r11)
/* Get a stable timebase and save it */ 1: mftbu r4 - stw r4,SL_TB(r1) + stw r4,SL_TB(r11) mftb r5 - stw r5,SL_TB+4(r1) + stw r5,SL_TB+4(r11) mftbu r3 cmpw r3,r4 bne 1b
/* Save SPRGs */ mfsprg r4,0 - stw r4,SL_SPRG0(r1) + stw r4,SL_SPRG0(r11) mfsprg r4,1 - stw r4,SL_SPRG0+4(r1) + stw r4,SL_SPRG0+4(r11) mfsprg r4,2 - stw r4,SL_SPRG0+8(r1) + stw r4,SL_SPRG0+8(r11) mfsprg r4,3 - stw r4,SL_SPRG0+12(r1) + stw r4,SL_SPRG0+12(r11)
/* Save BATs */ mfdbatu r4,0 - stw r4,SL_DBAT0(r1) + stw r4,SL_DBAT0(r11) mfdbatl r4,0 - stw r4,SL_DBAT0+4(r1) + stw r4,SL_DBAT0+4(r11) mfdbatu r4,1 - stw r4,SL_DBAT1(r1) + stw r4,SL_DBAT1(r11) mfdbatl r4,1 - stw r4,SL_DBAT1+4(r1) + stw r4,SL_DBAT1+4(r11) mfdbatu r4,2 - stw r4,SL_DBAT2(r1) + stw r4,SL_DBAT2(r11) mfdbatl r4,2 - stw r4,SL_DBAT2+4(r1) + stw r4,SL_DBAT2+4(r11) mfdbatu r4,3 - stw r4,SL_DBAT3(r1) + stw r4,SL_DBAT3(r11) mfdbatl r4,3 - stw r4,SL_DBAT3+4(r1) + stw r4,SL_DBAT3+4(r11) mfibatu r4,0 - stw r4,SL_IBAT0(r1) + stw r4,SL_IBAT0(r11) mfibatl r4,0 - stw r4,SL_IBAT0+4(r1) + stw r4,SL_IBAT0+4(r11) mfibatu r4,1 - stw r4,SL_IBAT1(r1) + stw r4,SL_IBAT1(r11) mfibatl r4,1 - stw r4,SL_IBAT1+4(r1) + stw r4,SL_IBAT1+4(r11) mfibatu r4,2 - stw r4,SL_IBAT2(r1) + stw r4,SL_IBAT2(r11) mfibatl r4,2 - stw r4,SL_IBAT2+4(r1) + stw r4,SL_IBAT2+4(r11) mfibatu r4,3 - stw r4,SL_IBAT3(r1) + stw r4,SL_IBAT3(r11) mfibatl r4,3 - stw r4,SL_IBAT3+4(r1) + stw r4,SL_IBAT3+4(r11)
BEGIN_MMU_FTR_SECTION mfspr r4,SPRN_DBAT4U - stw r4,SL_DBAT4(r1) + stw r4,SL_DBAT4(r11) mfspr r4,SPRN_DBAT4L - stw r4,SL_DBAT4+4(r1) + stw r4,SL_DBAT4+4(r11) mfspr r4,SPRN_DBAT5U - stw r4,SL_DBAT5(r1) + stw r4,SL_DBAT5(r11) mfspr r4,SPRN_DBAT5L - stw r4,SL_DBAT5+4(r1) + stw r4,SL_DBAT5+4(r11) mfspr r4,SPRN_DBAT6U - stw r4,SL_DBAT6(r1) + stw r4,SL_DBAT6(r11) mfspr r4,SPRN_DBAT6L - stw r4,SL_DBAT6+4(r1) + stw r4,SL_DBAT6+4(r11) mfspr r4,SPRN_DBAT7U - stw r4,SL_DBAT7(r1) + stw r4,SL_DBAT7(r11) mfspr r4,SPRN_DBAT7L - stw r4,SL_DBAT7+4(r1) + stw r4,SL_DBAT7+4(r11) mfspr r4,SPRN_IBAT4U - stw r4,SL_IBAT4(r1) + stw r4,SL_IBAT4(r11) mfspr r4,SPRN_IBAT4L - stw r4,SL_IBAT4+4(r1) + stw r4,SL_IBAT4+4(r11) mfspr r4,SPRN_IBAT5U - stw r4,SL_IBAT5(r1) + stw r4,SL_IBAT5(r11) mfspr r4,SPRN_IBAT5L - stw r4,SL_IBAT5+4(r1) + stw r4,SL_IBAT5+4(r11) mfspr r4,SPRN_IBAT6U - stw r4,SL_IBAT6(r1) + stw r4,SL_IBAT6(r11) mfspr r4,SPRN_IBAT6L - stw r4,SL_IBAT6+4(r1) + stw r4,SL_IBAT6+4(r11) mfspr r4,SPRN_IBAT7U - stw r4,SL_IBAT7(r1) + stw r4,SL_IBAT7(r11) mfspr r4,SPRN_IBAT7L - stw r4,SL_IBAT7+4(r1) + stw r4,SL_IBAT7+4(r11) END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
/* Backup various CPU config stuffs */ @@ -180,9 +183,9 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) lis r5,grackle_wake_up@ha addi r5,r5,grackle_wake_up@l tophys(r5,r5) - stw r5,SL_PC(r1) + stw r5,SL_PC(r11) lis r4,KERNELBASE@h - tophys(r5,r1) + tophys(r5,r11) addi r5,r5,SL_PC lis r6,MAGIC@ha addi r6,r6,MAGIC@l @@ -194,12 +197,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) tophys(r3,r3) stw r3,0x80(r4) stw r5,0x84(r4) - /* Store a pointer to our backup storage into - * a kernel global - */ - lis r3,sleep_storage@ha - addi r3,r3,sleep_storage@l - stw r5,0(r3)
.globl low_cpu_offline_self low_cpu_offline_self: @@ -279,7 +276,7 @@ _GLOBAL(core99_wake_up) lis r3,sleep_storage@ha addi r3,r3,sleep_storage@l tophys(r3,r3) - lwz r1,0(r3) + addi r1,r3,SL_PC
/* Pass thru to older resume code ... */ _ASM_NOKPROBE_SYMBOL(core99_wake_up) @@ -399,13 +396,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) blt 1b sync
- /* restore the MSR and turn on the MMU */ - lwz r3,SL_MSR(r1) - bl turn_on_mmu - - /* get back the stack pointer */ - tovirt(r1,r1) - /* Restore TB */ li r3,0 mttbl r3 @@ -419,28 +409,24 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) mtcr r0 lwz r2,SL_R2(r1) lmw r12,SL_R12(r1) - addi r1,r1,SL_SIZE - lwz r0,4(r1) - mtlr r0 - blr -_ASM_NOKPROBE_SYMBOL(grackle_wake_up)
-turn_on_mmu: - mflr r4 - tovirt(r4,r4) + /* restore the MSR and SP and turn on the MMU and return */ + lwz r3,SL_MSR(r1) + lwz r4,SL_LR(r1) + lwz r1,SL_SP(r1) mtsrr0 r4 mtsrr1 r3 sync isync rfi -_ASM_NOKPROBE_SYMBOL(turn_on_mmu) +_ASM_NOKPROBE_SYMBOL(grackle_wake_up)
#endif /* defined(CONFIG_PM) || defined(CONFIG_CPU_FREQ) */
- .section .data + .section .bss .balign L1_CACHE_BYTES sleep_storage: - .long 0 + .space SL_SIZE .balign L1_CACHE_BYTES, 0
#endif /* CONFIG_PPC_BOOK3S_32 */