From 65883b78bc9f49ac891bb202c59fcb76b9cfc611 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 21 Mar 2022 16:44:45 +0100 Subject: [PATCH] powerpc: align address to page boundary in change_page_attr() Aligning address to page boundary allows flush_tlb_kernel_range() to know it's a single page flush and use tlbie instead of tlbia. On 603 we now have the following code in first leg of change_page_attr(): 2c: 55 29 00 3c rlwinm r9,r9,0,0,30 30: 91 23 00 00 stw r9,0(r3) 34: 7c 00 22 64 tlbie r4,r0 38: 7c 00 04 ac hwsync 3c: 38 60 00 00 li r3,0 40: 4e 80 00 20 blr Before we had: 28: 55 29 00 3c rlwinm r9,r9,0,0,30 2c: 91 23 00 00 stw r9,0(r3) 30: 54 89 00 26 rlwinm r9,r4,0,0,19 34: 38 84 10 00 addi r4,r4,4096 38: 7c 89 20 50 subf r4,r9,r4 3c: 28 04 10 00 cmplwi r4,4096 40: 41 81 00 30 bgt 70 44: 7c 00 4a 64 tlbie r9,r0 48: 7c 00 04 ac hwsync 4c: 38 60 00 00 li r3,0 50: 4e 80 00 20 blr ... 70: 94 21 ff f0 stwu r1,-16(r1) 74: 7c 08 02 a6 mflr r0 78: 90 01 00 14 stw r0,20(r1) 7c: 48 00 00 01 bl 7c 7c: R_PPC_REL24 _tlbia 80: 80 01 00 14 lwz r0,20(r1) 84: 38 60 00 00 li r3,0 88: 7c 08 03 a6 mtlr r0 8c: 38 21 00 10 addi r1,r1,16 90: 4e 80 00 20 blr Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/6bb118fb2ee89fa3c1f9cf90ed19f88220002cb0.1647877467.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/pageattr.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c index 85753e32a4de..6163e484bc6d 100644 --- a/arch/powerpc/mm/pageattr.c +++ b/arch/powerpc/mm/pageattr.c @@ -31,6 +31,7 @@ static int change_page_attr(pte_t *ptep, unsigned long addr, void *data) { long action = (long)data; + addr &= PAGE_MASK; /* modify the PTE bits as desired */ switch (action) { case SET_MEMORY_RO: