From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932800Ab3BYWV3 (ORCPT ); Mon, 25 Feb 2013 17:21:29 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55333 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932669Ab3BYWUg (ORCPT ); Mon, 25 Feb 2013 17:20:36 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Meelis Roos , "David S. Miller" Subject: [ 58/58] sparc64: Fix huge PMD to PTE translation for sun4u in TLB miss handler. Date: Mon, 25 Feb 2013 14:19:54 -0800 Message-Id: <20130225221648.578322999@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130225221636.018756060@linuxfoundation.org> References: <20130225221636.018756060@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: "David S. Miller" [ 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(-) --- 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 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 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; \