From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AF27718B462; Tue, 10 Sep 2024 10:34:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725964478; cv=none; b=HStxg44bmfxMkumqTVuk0RGVVlFgYDOcENJzCjr0DHLFkSZwYm3KNDXfKFn7Qwvc091hDPozIoHsHxTaDncYtKPJA/ERCsm0to2BZ3/VfS/EsYeWOUS71wNntEVF/DzP+yqMyni2sPbuN/82QMC7Txa/jhAJjkI5dO/FVjD2wuM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725964478; c=relaxed/simple; bh=8suC4PMMCm6AFIMZYmMkG6BSihA1xyRVLFeT9QPv6Q4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gpBaYwIRfFSKqIIgAw9esc2RQjZpdvZUf2vAamF+tbnLVXLThBpfDw3XOIsAMOldlX1EEdHorUfiOwYXyRycHfuTz+a+wa+YFQNEceDkYXIavrlWl9nrAST7MjUgCLqVkstNMd3NOZAjH3+t1mJu2b4IqMc36xVaFZP773oyIq8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JVfxRVRd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="JVfxRVRd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 37884C4CEC3; Tue, 10 Sep 2024 10:34:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725964478; bh=8suC4PMMCm6AFIMZYmMkG6BSihA1xyRVLFeT9QPv6Q4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JVfxRVRdf0AK3AJeVVKIeoUS4nQY1VIThPXRdB9KJ7YmdP4Bml3hak3ZoEGKz4nwO dI4HjRQ5RKn7jX8in/skNFoZfO/ZtpYDBZgA3BCfn6fhNadCI11a46Zg+FHgHpYwAv GDcrt4+B066i/yKqk+5N06odhphq6jmcqjn7GMzc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexandre Ghiti , Palmer Dabbelt , WangYuli Subject: [PATCH 6.6 196/269] riscv: Use WRITE_ONCE() when setting page table entries Date: Tue, 10 Sep 2024 11:33:03 +0200 Message-ID: <20240910092615.094075592@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240910092608.225137854@linuxfoundation.org> References: <20240910092608.225137854@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Ghiti commit c30fa83b49897e708a52e122dd10616a52a4c82b upstream. To avoid any compiler "weirdness" when accessing page table entries which are concurrently modified by the HW, let's use WRITE_ONCE() macro (commit 20a004e7b017 ("arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables") gives a great explanation with more details). Signed-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20231213203001.179237-2-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt Signed-off-by: WangYuli Signed-off-by: Greg Kroah-Hartman --- arch/riscv/include/asm/pgtable-64.h | 6 +++--- arch/riscv/include/asm/pgtable.h | 4 ++-- 2 files changed, 5 insertions(+), 5 deletions(-) --- a/arch/riscv/include/asm/pgtable-64.h +++ b/arch/riscv/include/asm/pgtable-64.h @@ -198,7 +198,7 @@ static inline int pud_user(pud_t pud) static inline void set_pud(pud_t *pudp, pud_t pud) { - *pudp = pud; + WRITE_ONCE(*pudp, pud); } static inline void pud_clear(pud_t *pudp) @@ -274,7 +274,7 @@ static inline unsigned long _pmd_pfn(pmd static inline void set_p4d(p4d_t *p4dp, p4d_t p4d) { if (pgtable_l4_enabled) - *p4dp = p4d; + WRITE_ONCE(*p4dp, p4d); else set_pud((pud_t *)p4dp, (pud_t){ p4d_val(p4d) }); } @@ -347,7 +347,7 @@ static inline pud_t *pud_offset(p4d_t *p static inline void set_pgd(pgd_t *pgdp, pgd_t pgd) { if (pgtable_l5_enabled) - *pgdp = pgd; + WRITE_ONCE(*pgdp, pgd); else set_p4d((p4d_t *)pgdp, (p4d_t){ pgd_val(pgd) }); } --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -248,7 +248,7 @@ static inline int pmd_leaf(pmd_t pmd) static inline void set_pmd(pmd_t *pmdp, pmd_t pmd) { - *pmdp = pmd; + WRITE_ONCE(*pmdp, pmd); } static inline void pmd_clear(pmd_t *pmdp) @@ -515,7 +515,7 @@ static inline int pte_same(pte_t pte_a, */ static inline void set_pte(pte_t *ptep, pte_t pteval) { - *ptep = pteval; + WRITE_ONCE(*ptep, pteval); } void flush_icache_pte(pte_t pte);