From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:46960 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726700AbeJKXOG (ORCPT ); Thu, 11 Oct 2018 19:14:06 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christophe Leroy , Michael Ellerman Subject: [PATCH 4.14 35/45] powerpc/lib: fix book3s/32 boot failure due to code patching Date: Thu, 11 Oct 2018 17:40:02 +0200 Message-Id: <20181011152510.450697383@linuxfoundation.org> In-Reply-To: <20181011152508.885515042@linuxfoundation.org> References: <20181011152508.885515042@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christophe Leroy commit b45ba4a51cde29b2939365ef0c07ad34c8321789 upstream. Commit 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections") accesses 'init_mem_is_free' flag too early, before the kernel is relocated. This provokes early boot failure (before the console is active). As it is not necessary to do this verification that early, this patch moves the test into patch_instruction() instead of __patch_instruction(). This modification also has the advantage of avoiding unnecessary remappings. Fixes: 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections") Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/lib/code-patching.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -28,12 +28,6 @@ static int __patch_instruction(unsigned { int err; - /* Make sure we aren't patching a freed init section */ - if (init_mem_is_free && init_section_contains(exec_addr, 4)) { - pr_debug("Skipping init section patching addr: 0x%px\n", exec_addr); - return 0; - } - __put_user_size(instr, patch_addr, 4, err); if (err) return err; @@ -148,7 +142,7 @@ static inline int unmap_patch_area(unsig return 0; } -int patch_instruction(unsigned int *addr, unsigned int instr) +static int do_patch_instruction(unsigned int *addr, unsigned int instr) { int err; unsigned int *patch_addr = NULL; @@ -188,12 +182,22 @@ out: } #else /* !CONFIG_STRICT_KERNEL_RWX */ -int patch_instruction(unsigned int *addr, unsigned int instr) +static int do_patch_instruction(unsigned int *addr, unsigned int instr) { return raw_patch_instruction(addr, instr); } #endif /* CONFIG_STRICT_KERNEL_RWX */ + +int patch_instruction(unsigned int *addr, unsigned int instr) +{ + /* Make sure we aren't patching a freed init section */ + if (init_mem_is_free && init_section_contains(addr, 4)) { + pr_debug("Skipping init section patching addr: 0x%px\n", addr); + return 0; + } + return do_patch_instruction(addr, instr); +} NOKPROBE_SYMBOL(patch_instruction); int patch_branch(unsigned int *addr, unsigned long target, int flags)