From a97dd9e2f760c6996a8f1385ddab0bfef325b364 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 15 Oct 2021 12:02:45 +0200 Subject: [PATCH] powerpc/fsl_booke: Enable reloading of TLBCAM without switching to AS1 Avoid switching to AS1 when reloading TLBCAM after init for STRICT_KERNEL_RWX. When we setup AS1 we expect the entire accessible memory to be mapped through one entry, this is not the case anymore at the end of init. We are not changing the size of TLBCAMs, only flags, so no need to switch to AS1. So change loadcam_multi() to not switch to AS1 when the given temporary tlb entry in 0. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/a9d517fbfbc940f56103c46b323f6eb8f4485571.1634292136.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/nohash/tlb_low.S | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/nohash/tlb_low.S b/arch/powerpc/mm/nohash/tlb_low.S index 5add4a51e51f..dd39074de9af 100644 --- a/arch/powerpc/mm/nohash/tlb_low.S +++ b/arch/powerpc/mm/nohash/tlb_low.S @@ -369,7 +369,7 @@ _GLOBAL(_tlbivax_bcast) * extern void loadcam_entry(unsigned int index) * * Load TLBCAM[index] entry in to the L2 CAM MMU - * Must preserve r7, r8, r9, r10 and r11 + * Must preserve r7, r8, r9, r10, r11, r12 */ _GLOBAL(loadcam_entry) mflr r5 @@ -401,7 +401,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS) * * r3 = first entry to write * r4 = number of entries to write - * r5 = temporary tlb entry + * r5 = temporary tlb entry (0 means no switch to AS1) */ _GLOBAL(loadcam_multi) mflr r8 @@ -409,6 +409,8 @@ _GLOBAL(loadcam_multi) mfmsr r11 andi. r11,r11,MSR_IS bne 10f + mr. r12, r5 + beq 10f /* * Set up temporary TLB entry that is the same as what we're @@ -446,6 +448,8 @@ _GLOBAL(loadcam_multi) /* Don't return to AS=0 if we were in AS=1 at function start */ andi. r11,r11,MSR_IS bne 3f + cmpwi r12, 0 + beq 3f /* Return to AS=0 and clear the temporary entry */ mfmsr r6