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 7B33F8498 for ; Thu, 31 Aug 2023 11:12:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F28FCC433C9; Thu, 31 Aug 2023 11:12:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1693480344; bh=YObumt3eHckTNvyTsTNsInt8TltWDcWG5NHtU+jJcVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qk8wJ35J/P7bzQ6aCXkSEcHCykZ4AqaUZqEVBXtJlXNPj2IG+NI2AeU422vNHhFsR sS/2QmTC94UyxbaBwfA0iQjdKZGLuY/eF7t2qshU5nh6QPpRkh807VFaaPz8RD6gjk MmKbqJs+CFQV4p7DS3jUAepwrwb5YLKtbrgLP0HA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrea Righi , Luis Chamberlain Subject: [PATCH 6.4 2/9] module/decompress: use vmalloc() for zstd decompression workspace Date: Thu, 31 Aug 2023 13:11:29 +0200 Message-ID: <20230831111127.784527986@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230831111127.667900990@linuxfoundation.org> References: <20230831111127.667900990@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrea Righi commit a419beac4a070aff63c520f36ebf7cb8a76a8ae5 upstream. Using kmalloc() to allocate the decompression workspace for zstd may trigger the following warning when large modules are loaded (i.e., xfs): [ 2.961884] WARNING: CPU: 1 PID: 254 at mm/page_alloc.c:4453 __alloc_pages+0x2c3/0x350 ... [ 2.989033] Call Trace: [ 2.989841] [ 2.990614] ? show_regs+0x6d/0x80 [ 2.991573] ? __warn+0x89/0x160 [ 2.992485] ? __alloc_pages+0x2c3/0x350 [ 2.993520] ? report_bug+0x17e/0x1b0 [ 2.994506] ? handle_bug+0x51/0xa0 [ 2.995474] ? exc_invalid_op+0x18/0x80 [ 2.996469] ? asm_exc_invalid_op+0x1b/0x20 [ 2.997530] ? module_zstd_decompress+0xdc/0x2a0 [ 2.998665] ? __alloc_pages+0x2c3/0x350 [ 2.999695] ? module_zstd_decompress+0xdc/0x2a0 [ 3.000821] __kmalloc_large_node+0x7a/0x150 [ 3.001920] __kmalloc+0xdb/0x170 [ 3.002824] module_zstd_decompress+0xdc/0x2a0 [ 3.003857] module_decompress+0x37/0xc0 [ 3.004688] init_module_from_file+0xd0/0x100 [ 3.005668] idempotent_init_module+0x11c/0x2b0 [ 3.006632] __x64_sys_finit_module+0x64/0xd0 [ 3.007568] do_syscall_64+0x59/0x90 [ 3.008373] ? ksys_read+0x73/0x100 [ 3.009395] ? exit_to_user_mode_prepare+0x30/0xb0 [ 3.010531] ? syscall_exit_to_user_mode+0x37/0x60 [ 3.011662] ? do_syscall_64+0x68/0x90 [ 3.012511] ? do_syscall_64+0x68/0x90 [ 3.013364] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 However, continuous physical memory does not seem to be required in module_zstd_decompress(), so use vmalloc() instead, to prevent the warning and avoid potential failures at loading compressed modules. Fixes: 169a58ad824d ("module/decompress: Support zstd in-kernel decompression") Signed-off-by: Andrea Righi Signed-off-by: Luis Chamberlain Signed-off-by: Greg Kroah-Hartman --- kernel/module/decompress.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/module/decompress.c +++ b/kernel/module/decompress.c @@ -241,7 +241,7 @@ static ssize_t module_zstd_decompress(st } wksp_size = zstd_dstream_workspace_bound(header.windowSize); - wksp = kmalloc(wksp_size, GFP_KERNEL); + wksp = vmalloc(wksp_size); if (!wksp) { retval = -ENOMEM; goto out; @@ -284,7 +284,7 @@ static ssize_t module_zstd_decompress(st retval = new_size; out: - kfree(wksp); + vfree(wksp); return retval; } #else