From 4cd669a49791eb08742f24e0e62128e4d65159d7 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 20 Feb 2013 12:38:40 -0800 Subject: [PATCH] sparc64: Fix huge PMD to PTE translation for sun4u in TLB miss handler. [ Upstream commit 76968ad2eac6456270353de168b21f04f4b3d1d3 ] When we set the sun4u version of the PTE execute bit, it's: or REG, _PAGE_EXEC_4U, REG _PAGE_EXEC_4U is 0x1000, unfortunately the immedate field of the 'or' instruction is a signed 13-bit value. So the above actually assembles into: or REG, -4096, REG completely corrupting the final PTE value. Set it with a: sethi %hi(_PAGE_EXEC_4U), TMP or REG, TMP, REG sequence instead. This fixes "git gc" crashes on sun4u machines. Reported-by: Meelis Roos Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- arch/sparc/include/asm/tsb.h | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) diff --git a/arch/sparc/include/asm/tsb.h b/arch/sparc/include/asm/tsb.h index b4c258de4443..e696432b950d 100644 --- a/arch/sparc/include/asm/tsb.h +++ b/arch/sparc/include/asm/tsb.h @@ -157,17 +157,26 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end; andn REG2, 0x7, REG2; \ add REG1, REG2, REG1; - /* This macro exists only to make the PMD translator below easier - * to read. It hides the ELF section switch for the sun4v code - * patching. + /* These macros exists only to make the PMD translator below + * easier to read. It hides the ELF section switch for the + * sun4v code patching. */ -#define OR_PTE_BIT(REG, NAME) \ +#define OR_PTE_BIT_1INSN(REG, NAME) \ 661: or REG, _PAGE_##NAME##_4U, REG; \ .section .sun4v_1insn_patch, "ax"; \ .word 661b; \ or REG, _PAGE_##NAME##_4V, REG; \ .previous; +#define OR_PTE_BIT_2INSN(REG, TMP, NAME) \ +661: sethi %hi(_PAGE_##NAME##_4U), TMP; \ + or REG, TMP, REG; \ + .section .sun4v_2insn_patch, "ax"; \ + .word 661b; \ + mov -1, TMP; \ + or REG, _PAGE_##NAME##_4V, REG; \ + .previous; + /* Load into REG the PTE value for VALID, CACHE, and SZHUGE. */ #define BUILD_PTE_VALID_SZHUGE_CACHE(REG) \ 661: sethi %uhi(_PAGE_VALID|_PAGE_SZHUGE_4U), REG; \ @@ -214,12 +223,13 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end; andn REG1, PMD_HUGE_PROTBITS, REG2; \ sllx REG2, PMD_PADDR_SHIFT, REG2; \ /* REG2 now holds PFN << PAGE_SHIFT */ \ - andcc REG1, PMD_HUGE_EXEC, %g0; \ - bne,a,pt %xcc, 1f; \ - OR_PTE_BIT(REG2, EXEC); \ -1: andcc REG1, PMD_HUGE_WRITE, %g0; \ + andcc REG1, PMD_HUGE_WRITE, %g0; \ bne,a,pt %xcc, 1f; \ - OR_PTE_BIT(REG2, W); \ + OR_PTE_BIT_1INSN(REG2, W); \ +1: andcc REG1, PMD_HUGE_EXEC, %g0; \ + be,pt %xcc, 1f; \ + nop; \ + OR_PTE_BIT_2INSN(REG2, REG1, EXEC); \ /* REG1 can now be clobbered, build final PTE */ \ 1: BUILD_PTE_VALID_SZHUGE_CACHE(REG1); \ ba,pt %xcc, PTE_LABEL; \ -- 2.39.5