From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bg5.exmail.qq.com (bg5.exmail.qq.com [43.154.197.177]) (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 C05522E093F for ; Fri, 12 Dec 2025 09:59:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=43.154.197.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765533572; cv=none; b=GXeZfNPsOnJ7CKWZqVAxoh9UnzozczMpr+lpk0Xdrb01vLep5bliHtiEKQvrnDrgLrzENxj2/QmyQ50UdcFfRwDHtUnJYRoSaCmlpKot7Vc9hfMBRBjD7rPQMUzxnBzvm3PAoOKgxVBZPs83j215vUwdmGrbAbGuILC//Py08UY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765533572; c=relaxed/simple; bh=vrehtkBoQOzy8lwGiRQts9N6alDa1iI40cabkPUNC6g=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=CI3+wNnLcuNMAN0+kpIJyXcDoP8FfgqfYPSPz42/9gGj9oOGHCj1Tg6C4rlgb1a0TF/O/1AbFNYhY8w2Lxo7P/6K9cDWisZ0ba4UFDGdNG+Wvd92S2gp5sxUk1nZK6bp8hH3wOaYQEKdRRy8QA69DzS532QEe5ghLUImYh1AETs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com; spf=pass smtp.mailfrom=uniontech.com; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b=DLxKrj+Y; arc=none smtp.client-ip=43.154.197.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=uniontech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=uniontech.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=uniontech.com header.i=@uniontech.com header.b="DLxKrj+Y" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=uniontech.com; s=onoh2408; t=1765533469; bh=8t5l/NtY1SYKroL5Up7y+J2/044lu/7/n00xq6dNOOA=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=DLxKrj+YXIWP60bu95WlRRF7s9/8R98UORz0fnvunJct8vR4r7mJzx9t8/FmyLN/j sV6dWSNm8wehYylKpeJDddBm/XeqJ4MGIG/h9ztuFJDKmq9vu5fJ5S1uXgQZxt612T /eofNkNFANv39kgIAYcKfAur3dCnRjTcgZr3UIpw= X-QQ-mid: esmtpsz10t1765533451t8d6bfcab X-QQ-Originating-IP: 2LL2NMRf384R8803vL8zyY/tfZxKKcLdRzEhyMActVE= Received: from localhost.localdomain ( [123.114.60.34]) by bizesmtp.qq.com (ESMTP) with id ; Fri, 12 Dec 2025 17:57:29 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 1 X-BIZMAIL-ID: 17493561031985165414 EX-QQ-RecipientCnt: 8 From: Qiang Ma To: akpm@linux-foundation.org, bhe@redhat.com, catalin.marinas@arm.com, will@kernel.org Cc: kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Qiang Ma Subject: [PATCH v1 0/3] kexec: add kexec flag to control debug printing Date: Fri, 12 Dec 2025 17:56:46 +0800 Message-Id: <20251212095649.857796-1-maqianga@uniontech.com> X-Mailer: git-send-email 2.20.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: esmtpsz:uniontech.com:qybglogicsvrsz:qybglogicsvrsz3b-0 X-QQ-XMAILINFO: OBgljwTFJiVqCzOE8KnwiL0jG8W2ZXx20S8b1PlVL1mca18tbtopOIpL SJCHcJgvD3rJBViW1W22+qsAwExdGoRRym75xgRZmIpT9kD6E03WDDI8nUBedCPY5TBMHf3 XupTms+QB+iG8r8iNOy03aOQtTrTbsKvOZNUP9Sj7cwlm4ilv3hCquwmfWdaVqrywcLToSu xZQJ2jkvuxlYU7fTrSRyRPOXqnZ0o39iyBg+ayJJCm77OR4S/tcyYY+4ciZDnmhhgkMNyMV Xg/U3S7l4KUs+nKbpHM3wVXY5WISD6IvxidnQROz2xWvqQbN10M54Q/ajqob0HLfeX7jdaC BHeuXetCJQB7lUiqd0wjiNqaEYcD2Q7O8IDvp8IMZQGXNVm6BIBHgecgVpkrjSno0xUZTYW UOiMPebB3KfBnFOXu+NKeQw9gvhUdhKIBFLY6Fqw6CAXm+Oa3mnUA7YZT1oWuzFejaW2Y0Z PLR252QfdFCdMqhRGvX329Knl8PLyhuJ17i5FmBVAJRGEA3d594hGJ79HCyhBpDT7qFl8B7 tWKWlrPLdCIIXzIXW0q93/NHiIW5i1iSICAsLbFW9LcVW+ut5KC6JgIh6Dcl2HT2VBi4qDN 1TWeoBicG4Xwp6stQhOuSg0F3ua5kk9e5llSbpp/aYPIBkJDd2/T5sgdHxocEvrVzDkcq+S KjRdU8VTQw4o3WapJxlLNfk40c8QZkZGBEUeE/vtpm7nPb9IiqN578yp3mwx9QSed/D+Ar+ RszpodW7wW6PlHF7HCzZgYEGpAIspRo1DvRla7EHKZAQIRtmc+JWjUknHfZN3e6RyPe+zT+ zfXngBTmrvtV+vsRdZ9inNVGq2hEmsvP0ctsLIxkTbZBj+/gpIiQw0Jf5GWMhJSVhOTgfPd W8JK2SbH8qZlI/CL+iEZF1jVkDk7La5amgdFFKhv1ZIpvdAUYQZgTwS1cvGKBhuaoDRRa/3 XN90xkgbYttDFOeFxe7BP9OA4N5FilMARd9FYyRKJd/WsT3M7CVYuBiwWgpjyfzAJXh7QYT xPgTfWBX8QIOsLSFE4RyFUwJiUFxD6Rjd+VI1vOl+4/WjSfnpTv7amFW3h4Js0JLbvRbRtO A== X-QQ-XMRINFO: NS+P29fieYNw95Bth2bWPxk= X-QQ-RECHKSPAM: 0 Overview: ========= The commit cbc2fe9d9cb2 ("kexec_file: add kexec_file flag to control debug printing") added the kexec_file flag to control debug printing. However, for arm64, after commit 6f8c1da071a4 ("kexec_file, arm64: print out debugging message if required"), when using the kexec_load interface, the kexec_image_info function is called to print debug message, but it uses kexec_dprintk, which is only available under kexec_file, then when specifying 'kexec -d', kexec_load interface will print nothing. For riscv, commit eb7622d908a09 ("kexec_file, riscv: print out debugging message if required") remove kexec_image_info(), because the content has been printed out in generic code in kexec_file_load, but not in kexec_load. Therefore, in order to solve the two problems mentioned above, for this patchset, several things need to be done: 1. Enabling kexec_dprintk is available for kexec_load. 2. Add some debugging message of the deleted kexec_image_info to generic code. 3. Remove duplicate debugging prints for arm64. Since kexec_load and kexec_file_load are not triggered simultaneously, we can unify the debug flag of kexec and kexec_file as kexec_dbg_print. In this way, kexec_dprintk is available for kexec_load and kexec_file_load. Then when specifying 'kexec -d', the debugging message using kexec_dprintk in kexec_image_info can be printed normally. The following are the key points of the specific changes: 1. rename kexec_file_dbg_print to kexec_dbg_print 2. Add KEXEC_DEBUG 3. Initialize kexec_dbg_print for kexec 4. Set the reset of kexec_dbg_print to kimage_free Testing: ========= I did testing on x86_64, arm64 and loongarch. On x86_64, the printed messages look like below: Unset CONFIG_KEXEC_FILE: [ 36.774228] kexec_file: kernel: 0000000066c386c8 kernel_size: 0xd78400 [ 36.821814] kexec-bzImage64: Loaded purgatory at 0x23fffb000 [ 36.821826] kexec-bzImage64: Loaded boot_param, command line and misc at 0x23fff9000 bufsz=0x12d0 memsz=0x2000 [ 36.821829] kexec-bzImage64: Loaded 64bit kernel at 0x23d400000 bufsz=0xd73400 memsz=0x2ab7000 [ 36.821918] kexec-bzImage64: Loaded initrd at 0x23bd0b000 bufsz=0x16f40a8 memsz=0x16f40a8 [ 36.821920] kexec-bzImage64: Final command line is: root=/dev/mapper/test-root crashkernel=auto rd.lvm.lv=test/root [ 36.821925] kexec-bzImage64: E820 memmap: [ 36.821926] kexec-bzImage64: 0000000000000000-000000000009ffff (1) [ 36.821928] kexec-bzImage64: 0000000000100000-0000000000811fff (1) [ 36.821930] kexec-bzImage64: 0000000000812000-0000000000812fff (2) [ 36.821931] kexec-bzImage64: 0000000000813000-00000000bee38fff (1) [ 36.821933] kexec-bzImage64: 00000000bee39000-00000000beec2fff (2) [ 36.821934] kexec-bzImage64: 00000000beec3000-00000000bf8ecfff (1) [ 36.821935] kexec-bzImage64: 00000000bf8ed000-00000000bfb6cfff (2) [ 36.821936] kexec-bzImage64: 00000000bfb6d000-00000000bfb7efff (3) [ 36.821937] kexec-bzImage64: 00000000bfb7f000-00000000bfbfefff (4) [ 36.821938] kexec-bzImage64: 00000000bfbff000-00000000bff7bfff (1) [ 36.821939] kexec-bzImage64: 00000000bff7c000-00000000bfffffff (2) [ 36.821940] kexec-bzImage64: 00000000feffc000-00000000feffffff (2) [ 36.821941] kexec-bzImage64: 00000000ffc00000-00000000ffffffff (2) [ 36.821942] kexec-bzImage64: 0000000100000000-000000023fffffff (1) [ 36.872348] kexec_file: nr_segments = 4 [ 36.872356] kexec_file: segment[0]: buf=0x000000005314ece7 bufsz=0x4000 mem=0x23fffb000 memsz=0x5000 [ 36.872370] kexec_file: segment[1]: buf=0x000000006e59b143 bufsz=0x12d0 mem=0x23fff9000 memsz=0x2000 [ 36.872374] kexec_file: segment[2]: buf=0x00000000eb7b1fc3 bufsz=0xd73400 mem=0x23d400000 memsz=0x2ab7000 [ 36.882172] kexec_file: segment[3]: buf=0x000000006af76441 bufsz=0x16f40a8 mem=0x23bd0b000 memsz=0x16f5000 [ 36.889113] kexec_file: kexec_file_load: type:0, start:0x23fffb150 head:0x101a2e002 flags:0x8 On aarch64, the printed messages look like below: Set CONFIG_KEXEC_FILE [ 39.033203] kexec_file: kernel: 0000000073414684 kernel_size: 0x3123a00 [ 39.047010] kexec_file: Loaded initrd at 0x43cf0000 bufsz=0x17e0e19 memsz=0x17e1000 [ 39.047054] kexec_file: Loaded dtb at 0x23ec00000 bufsz=0x386 memsz=0x1000 [ 39.047056] kexec_file(Image): Loaded kernel at 0x40000000 bufsz=0x3123a00 memsz=0x3cf0000 [ 39.047063] kexec_file: nr_segments = 3 [ 39.047064] kexec_file: segment[0]: buf=0x0000000073414684 bufsz=0x3123a00 mem=0x40000000 memsz=0x3cf0000 [ 39.073612] kexec_file: segment[1]: buf=0x000000005cd5746b bufsz=0x17e0e19 mem=0x43cf0000 memsz=0x17e1000 [ 39.085309] kexec_file: segment[2]: buf=0x0000000084c4a0f1 bufsz=0x386 mem=0x23ec00000 memsz=0x1000 [ 39.085459] machine_kexec_post_load:155: [ 39.085463] kexec kimage info: [ 39.085467] kern_reloc: 0x00000001620e2000 [ 39.085468] el2_vectors: 0x0000000000000000 [ 39.085470] kexec_file: kexec_file_load: type:0, start:0x40000000 head:0x1620e4002 flags:0x8 Unset CONFIG_KEXEC_FILE: With this patch: [ 35.156088] machine_kexec_post_load:155: [ 35.156097] kexec kimage info: [ 35.156101] kern_reloc: 0x000000011c134000 [ 35.156102] el2_vectors: 0x0000000000000000 [ 35.156104] kexec: kexec_load: type:0, start:0x454d26b0 head:0x105c14002 flags:0xb70010 Without this patch: There is no kexec print in dmesg. Previous posts: Link: https://lore.kernel.org/all/aTdxEvqY6Bcy7Wa1@MiWiFi-R3L-srv/ Qiang Ma (3): kexec: add kexec flag to control debug printing kexec: print out debugging message if required for kexec_load arm64: kexec: Adjust the debug print of kexec_image_info arch/arm64/kernel/machine_kexec.c | 2 -- include/linux/kexec.h | 9 +++++---- include/uapi/linux/kexec.h | 1 + kernel/kexec.c | 4 ++++ kernel/kexec_core.c | 4 +++- kernel/kexec_file.c | 4 +--- 6 files changed, 14 insertions(+), 10 deletions(-) -- 2.20.1