From 3f57d90c231d3329aaed7079dd05b5a2f7692a58 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 20 Aug 2024 19:23:57 +0200 Subject: [PATCH] powerpc/603: Inconditionally use task PGDIR in ITLB misses Now that modules exec page tables are preallocated, the instruction TLBmiss handler can use task PGDIR inconditionally. Also revise the identification of user vs kernel user space by doing a calculation instead of a comparison: Get the segment number and subtract the number of the first kernel segment. The result is positive for kernel addresses and negative for user addresses, which means that upper 2 bits are 0 for kernel and 3 for user. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/9a3242162ad2faab8019c698e501b326a126ee9e.1724173828.git.christophe.leroy@csgroup.eu --- arch/powerpc/kernel/head_book3s_32.S | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index 7995506e7fbd..156304c00ece 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -413,22 +413,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE) InstructionTLBMiss: /* Get PTE (linux-style) and check access */ mfspr r0,SPRN_IMISS -#ifdef CONFIG_EXECMEM - lis r1, TASK_SIZE@h /* check if kernel address */ - cmplw 0,r1,r0 -#endif mfspr r2, SPRN_SDR1 li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC rlwinm r2, r2, 28, 0xfffff000 + rlwimi r2,r0,12,20,29 /* insert top 10 bits of address */ + lwz r2,0(r2) /* get pmd entry */ #ifdef CONFIG_EXECMEM - li r3, 3 - bgt- 112f - lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ - li r3, 0 - addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */ + rlwinm r3, r0, 4, 0xf + subi r3, r3, (TASK_SIZE >> 28) & 0xf #endif -112: rlwimi r2,r0,12,20,29 /* insert top 10 bits of address */ - lwz r2,0(r2) /* get pmd entry */ rlwinm. r2,r2,0,0,19 /* extract address of pte page */ beq- InstructionAddressInvalid /* return if no mapping */ rlwimi r2,r0,22,20,29 /* insert next 10 bits of address */ @@ -437,7 +430,7 @@ InstructionTLBMiss: bne- InstructionAddressInvalid /* return if access not permitted */ /* Convert linux-style PTE to low word of PPC-style PTE */ #ifdef CONFIG_EXECMEM - rlwimi r2, r3, 0, 31, 31 /* userspace ? -> PP lsb */ + rlwimi r2, r3, 1, 31, 31 /* userspace ? -> PP lsb */ #endif ori r1, r1, 0xe06 /* clear out reserved bits */ andc r1, r2, r1 /* PP = user? 1 : 0 */ -- 2.25.1