{"id":2220052,"url":"http://patchwork.ozlabs.org/api/patches/2220052/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20260406061542.22354-1-litaliano00.contact@gmail.com/","project":{"id":2,"url":"http://patchwork.ozlabs.org/api/projects/2/?format=json","name":"Linux PPC development","link_name":"linuxppc-dev","list_id":"linuxppc-dev.lists.ozlabs.org","list_email":"linuxppc-dev@lists.ozlabs.org","web_url":"https://github.com/linuxppc/wiki/wiki","scm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git","webscm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/","list_archive_url":"https://lore.kernel.org/linuxppc-dev/","list_archive_url_format":"https://lore.kernel.org/linuxppc-dev/{}/","commit_url_format":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id={}"},"msgid":"<20260406061542.22354-1-litaliano00.contact@gmail.com>","list_archive_url":"https://lore.kernel.org/linuxppc-dev/20260406061542.22354-1-litaliano00.contact@gmail.com/","date":"2026-04-06T06:15:42","name":"powerpc/fadump: Add timeout to RTAS busy-wait loops","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"fe181193cda4246e659d4535fd9d290bac298d95","submitter":{"id":93067,"url":"http://patchwork.ozlabs.org/api/people/93067/?format=json","name":"litaliano00","email":"litaliano00.contact@gmail.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20260406061542.22354-1-litaliano00.contact@gmail.com/mbox/","series":[{"id":498825,"url":"http://patchwork.ozlabs.org/api/series/498825/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=498825","date":"2026-04-06T06:15:42","name":"powerpc/fadump: Add timeout to RTAS busy-wait loops","version":1,"mbox":"http://patchwork.ozlabs.org/series/498825/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2220052/comments/","check":"fail","checks":"http://patchwork.ozlabs.org/api/patches/2220052/checks/","tags":{},"related":[],"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=UKZnLDt6;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=2404:9400:21b9:f100::1; helo=lists.ozlabs.org;\n envelope-from=linuxppc-dev+bounces-19384-incoming=patchwork.ozlabs.org@lists.ozlabs.org;\n receiver=patchwork.ozlabs.org)","lists.ozlabs.org;\n arc=none smtp.remote-ip=\"2a00:1450:4864:20::32f\"","lists.ozlabs.org;\n dmarc=pass (p=none dis=none) header.from=gmail.com","lists.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=UKZnLDt6;\n\tdkim-atps=neutral","lists.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com\n (client-ip=2a00:1450:4864:20::32f; helo=mail-wm1-x32f.google.com;\n envelope-from=litaliano00.contact@gmail.com; receiver=lists.ozlabs.org)"],"Received":["from lists.ozlabs.org (lists.ozlabs.org\n [IPv6:2404:9400:21b9:f100::1])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1 raw public key)\n server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fq07z737rz1yFt\n\tfor ; Mon, 06 Apr 2026 16:40:31 +1000 (AEST)","from boromir.ozlabs.org (localhost [127.0.0.1])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 4fq07w5dDTz2yfl;\n\tMon, 06 Apr 2026 16:40:28 +1000 (AEST)","from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com\n [IPv6:2a00:1450:4864:20::32f])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest\n SHA256)\n\t(No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 4fpzcH542bz2ySV\n\tfor ; Mon, 06 Apr 2026 16:16:30 +1000 (AEST)","by mail-wm1-x32f.google.com with SMTP id\n 5b1f17b1804b1-4888244e9f9so33435235e9.0\n for ;\n Sun, 05 Apr 2026 23:16:30 -0700 (PDT)","from fedora.homenet.telecomitalia.it\n (host-82-53-109-192.retail.telecomitalia.it. [82.53.109.192])\n by smtp.gmail.com with ESMTPSA id\n 5b1f17b1804b1-488b6ff70bcsm26037455e9.14.2026.04.05.23.16.21\n (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256);\n Sun, 05 Apr 2026 23:16:21 -0700 (PDT)"],"ARC-Seal":"i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1775456193;\n\tcv=none;\n b=lHd4YM4pT2PrsdqHPFDJNZ6NTzlJ9VJCwfG+KYNWt352iiKOWch7+M2vh4UflTvIwXFPDoR8ZmpnxVdmxBqaSS2JvxRnsRbmEV+AamXmqzMhrDbI/KpwmzEc7DFBxEc0KwFTGx9/nNpb/EcwDiUMyqZ3/PzU3hbG1cShFvziwHKOBkNqlEHGiP18yHpLhLoy/+kE9Fne8du96vOHLOQQhZWS2AXH7P2JZolo4W59fLP0Ss+k5WJYFeyXBr8H3LDrsDlkKxClCtb4VB23XrVmv39+lwz1j4pJHSek5ohSBrAqG6Hhboh+mTPeRSzXj5DGMLA56POFhWFobJPmw6bnMA==","ARC-Message-Signature":"i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707;\n\tt=1775456193; c=relaxed/relaxed;\n\tbh=iazOb18zH09zHtasIHRjBS4gdZV9mNmxJwOYyWl7kAo=;\n\th=From:To:Cc:Subject:Date:Message-ID:MIME-Version;\n b=lX9VcaUFJdTXRow+5fv3VYz12JVUXOze9CnCCSFi0r7AGMt9jZzwBaAZp14Er3ZRLN3CnjIpGPGGbx7lNEtnWtpb6ZPUgLSOGyEPIGnNrBjDKLoQRa4ko45AMqW5aMQ4yighRBVzOucu1daQgD/Rjt9O1Lh+0w3+jiVOH1FcQnqQ+aSMrckNV9jxOfd6Pof3zFYRacQeMwQT+wmevL2y426giyeKYOQ3Eyx12veoXHVH0XWJ1am3uz0h2INb9w7ea1rTQbiXFw0j89748h/mS3CtfFYKhwaMinyosR0ocUuvlb0S9qA4UqKinskMV6hRqF1pAPTepnCW+ziCQkyUIw==","ARC-Authentication-Results":"i=1; lists.ozlabs.org;\n dmarc=pass (p=none dis=none) header.from=gmail.com; dkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=UKZnLDt6; dkim-atps=neutral;\n spf=pass (client-ip=2a00:1450:4864:20::32f; helo=mail-wm1-x32f.google.com;\n envelope-from=litaliano00.contact@gmail.com;\n receiver=lists.ozlabs.org) smtp.mailfrom=gmail.com","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n d=gmail.com; s=20251104; t=1775456182; x=1776060982;\n darn=lists.ozlabs.org;\n h=content-transfer-encoding:mime-version:message-id:date:subject:cc\n :to:from:from:to:cc:subject:date:message-id:reply-to;\n bh=iazOb18zH09zHtasIHRjBS4gdZV9mNmxJwOYyWl7kAo=;\n b=UKZnLDt6DvkbaKKpMJCu/0GvEIkFQeBCW/+QrWQs36a12d8NjAw9g/eb2zUY5MIRT9\n +eE3/Ok2r0x50Q46abWoZOVbaFsUJE8WKmd3BlWOr9dbp1MQA806XuXaFMLthSV2ghEi\n 7EDa2XiB3Cues+HSMiWQxpvZ65cj5bz90yC2F2xaSKXpQrQOBYfwKnhHLGNn7aNPEaYB\n wvjtqkpZLf+wDR+X4DmyiJ6yLinw6bTQfVOenC9hjuwmiQ0rclpqmtEkIHsFN2aRLuzA\n eEL7C0V0F6k5vNbugEHKEX+KLhbLEBRyz508IFePpl8JOziWqv9XIfWYQ0e2dg4xaqBD\n 5vNA==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n d=1e100.net; s=20251104; t=1775456182; x=1776060982;\n h=content-transfer-encoding:mime-version:message-id:date:subject:cc\n :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date\n :message-id:reply-to;\n bh=iazOb18zH09zHtasIHRjBS4gdZV9mNmxJwOYyWl7kAo=;\n b=izN2p7wmQ7PRqiRzRdoK2yli0fJvdw3+PfEUzIzbDtIpEbh9VHRLU9skkyrEBb7Pfu\n 4Ljp0RSS5IYxqPHP0cTP1JCEVfeGudQOrIxLad4XnQerw6lAO6Q/NSRao16HDQPeCT+I\n CPQHuoUSvzjToSUnmXj4Tkb70+kRA6bcVoOo1b/7b9kNov5UsMDEUwgz4GN3jnRJAmkr\n l9zwHjwaDLNu1Fjhd4W6ps94gnmrzOr/oVkh7AQSSJGYzhA4DNhjKWcVe3HRy289PDOR\n XU6z9Zemv1/Dn/dLB4YPD+FQBTGaLyrgDGeh+vTM0sZUMRqFwlq0rH0IdNwaWRgN4Go2\n Ow0Q==","X-Forwarded-Encrypted":"i=1;\n AJvYcCX5S8AdMTd+igNApgx8DkVKH0gK7g8Qg5EGJO8Q7m5nf8PMR0UFyDjIu+sJMiSux2fybMGDjsCzmQp0SEI=@lists.ozlabs.org","X-Gm-Message-State":"AOJu0YxKB5O11Cefqb4frDtLsx6T2dZIGSHGljxWKqiT4I9VycZeudNc\n\tibGsd7YEZPfqsnZhtBV1hhAZrSqcUGRMwKnmcB8RHPGFyaH0poKgcp3O","X-Gm-Gg":"AeBDieuUyOqv3DFCkMH9V8+Perz5XwD76MEvjeF+af/D0eOl6EcB8H7e0Vx9xeju2vk\n\tx+Z9y2l71cHVmOuOyZmdoKdmy8s/QJOzLnMDt4hB7jkVjGcr/oMkRzf43I4wdiIyPLhMhEJUab1\n\t5XwLeY+xdtmEorb75OlZxgPTJduLAj3ClKXEXp0v69/LQHo1JbswjmO4fQ7tIuPAS4cbzKqwzJI\n\tP02LALXPIBbH2dKLfN1gxvZc37vY2a/29lc1gV7h0s3aqtnd8IlOFjWFulmA6cWuyqvnLV9lPG1\n\tmCGEfdkcG/tdZnlYUa1oLAXHIADwan27MOy9DRLGdHlBpp7HG7uOdb3jFEFof1Z3AwQ6Mucb3ph\n\tzpFpeN8vxP/KEtAA6L8g79aWUHo/iGylTjSGxUnhRoaLw7ktzF6+ZTx78soVU0/Zc5HtW6AhjG2\n\t3aRRUSu5ypDI4/uNV/MOWnIkygH5AVoGJweb0/Gs5w6YKy/uowtJnzQPACDpzYsxj8r8D109UiV\n\tonJCWHf2OHGss+RdWryZAJTe47qt2xTtdRciA==","X-Received":"by 2002:a05:600d:8449:b0:487:1fbf:e0a1 with SMTP id\n 5b1f17b1804b1-488996a1e01mr127552785e9.4.1775456182266;\n Sun, 05 Apr 2026 23:16:22 -0700 (PDT)","From":"Adriano Vero ","To":"maddy@linux.ibm.com,\n\tmpe@ellerman.id.au","Cc":"npiggin@gmail.com,\n\tchleroy@kernel.org,\n\tlinuxppc-dev@lists.ozlabs.org,\n\tlinux-kernel@vger.kernel.org,\n\tAdriano Vero ","Subject":"[PATCH] powerpc/fadump: Add timeout to RTAS busy-wait loops","Date":"Mon, 6 Apr 2026 08:15:42 +0200","Message-ID":"<20260406061542.22354-1-litaliano00.contact@gmail.com>","X-Mailer":"git-send-email 2.53.0","X-Mailing-List":"linuxppc-dev@lists.ozlabs.org","List-Id":"","List-Help":"","List-Owner":"","List-Post":"","List-Archive":",\n ","List-Subscribe":",\n ,\n ","List-Unsubscribe":"","Precedence":"list","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Spam-Status":"No, score=-0.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID,\n\tDKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,\n\tSPF_HELO_NONE,SPF_PASS autolearn=disabled version=4.0.1 OzLabs 8","X-Spam-Checker-Version":"SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org"},"content":"The ibm,configure-kernel-dump RTAS call sites in\nrtas_fadump_register(), rtas_fadump_unregister(), and\nrtas_fadump_invalidate() polled indefinitely while firmware returned\na busy status. A misbehaving or hung firmware could stall these paths\nforever, blocking fadump registration at boot or preventing clean\nteardown.\n\nTrack the accumulated delay in a total_wait counter and bail out with\n-ETIMEDOUT if it reaches RTAS_FADUMP_MAX_WAIT_MS (60 seconds) before\nfirmware signals completion. This follows the bounded busy-wait pattern\nused in rtas-rtc.c.\n\nSigned-off-by: Adriano Vero \n---\n arch/powerpc/platforms/pseries/rtas-fadump.c | 37 ++++++++++++++------\n arch/powerpc/platforms/pseries/rtas-fadump.h | 6 ++++\n 2 files changed, 33 insertions(+), 10 deletions(-)","diff":"diff --git a/arch/powerpc/platforms/pseries/rtas-fadump.c b/arch/powerpc/platforms/pseries/rtas-fadump.c\nindex eceb32893..b165f165c 100644\n--- a/arch/powerpc/platforms/pseries/rtas-fadump.c\n+++ b/arch/powerpc/platforms/pseries/rtas-fadump.c\n@@ -181,7 +181,7 @@ static u64 rtas_fadump_get_bootmem_min(void)\n \n static int rtas_fadump_register(struct fw_dump *fadump_conf)\n {\n-\tunsigned int wait_time, fdm_size;\n+\tunsigned int wait_time, total_wait, fdm_size;\n \tint rc, err = -EIO;\n \n \t/*\n@@ -192,15 +192,20 @@ static int rtas_fadump_register(struct fw_dump *fadump_conf)\n \tfdm_size = sizeof(struct rtas_fadump_section_header);\n \tfdm_size += be16_to_cpu(fdm.header.dump_num_sections) * sizeof(struct rtas_fadump_section);\n \n-\t/* TODO: Add upper time limit for the delay */\n+\ttotal_wait = 0;\n \tdo {\n \t\trc = rtas_call(fadump_conf->ibm_configure_kernel_dump, 3, 1,\n \t\t\t\tNULL, FADUMP_REGISTER, &fdm, fdm_size);\n \n \t\twait_time = rtas_busy_delay_time(rc);\n-\t\tif (wait_time)\n+\t\tif (wait_time) {\n+\t\t\tif (total_wait >= RTAS_FADUMP_MAX_WAIT_MS) {\n+\t\t\t\tpr_err(\"Timed out waiting for firmware to register fadump\\n\");\n+\t\t\t\treturn -ETIMEDOUT;\n+\t\t\t}\n+\t\t\ttotal_wait += wait_time;\n \t\t\tmdelay(wait_time);\n-\n+\t\t}\n \t} while (wait_time);\n \n \tswitch (rc) {\n@@ -234,18 +239,24 @@ static int rtas_fadump_register(struct fw_dump *fadump_conf)\n \n static int rtas_fadump_unregister(struct fw_dump *fadump_conf)\n {\n-\tunsigned int wait_time;\n+\tunsigned int wait_time, total_wait;\n \tint rc;\n \n-\t/* TODO: Add upper time limit for the delay */\n+\ttotal_wait = 0;\n \tdo {\n \t\trc = rtas_call(fadump_conf->ibm_configure_kernel_dump, 3, 1,\n \t\t\t\tNULL, FADUMP_UNREGISTER, &fdm,\n \t\t\t\tsizeof(struct rtas_fadump_mem_struct));\n \n \t\twait_time = rtas_busy_delay_time(rc);\n-\t\tif (wait_time)\n+\t\tif (wait_time) {\n+\t\t\tif (total_wait >= RTAS_FADUMP_MAX_WAIT_MS) {\n+\t\t\t\tpr_err(\"Timed out waiting for firmware to unregister fadump\\n\");\n+\t\t\t\treturn -ETIMEDOUT;\n+\t\t\t}\n+\t\t\ttotal_wait += wait_time;\n \t\t\tmdelay(wait_time);\n+\t\t}\n \t} while (wait_time);\n \n \tif (rc) {\n@@ -259,18 +270,24 @@ static int rtas_fadump_unregister(struct fw_dump *fadump_conf)\n \n static int rtas_fadump_invalidate(struct fw_dump *fadump_conf)\n {\n-\tunsigned int wait_time;\n+\tunsigned int wait_time, total_wait;\n \tint rc;\n \n-\t/* TODO: Add upper time limit for the delay */\n+\ttotal_wait = 0;\n \tdo {\n \t\trc = rtas_call(fadump_conf->ibm_configure_kernel_dump, 3, 1,\n \t\t\t\tNULL, FADUMP_INVALIDATE, fdm_active,\n \t\t\t\tsizeof(struct rtas_fadump_mem_struct));\n \n \t\twait_time = rtas_busy_delay_time(rc);\n-\t\tif (wait_time)\n+\t\tif (wait_time) {\n+\t\t\tif (total_wait >= RTAS_FADUMP_MAX_WAIT_MS) {\n+\t\t\t\tpr_err(\"Timed out waiting for firmware to invalidate fadump\\n\");\n+\t\t\t\treturn -ETIMEDOUT;\n+\t\t\t}\n+\t\t\ttotal_wait += wait_time;\n \t\t\tmdelay(wait_time);\n+\t\t}\n \t} while (wait_time);\n \n \tif (rc) {\ndiff --git a/arch/powerpc/platforms/pseries/rtas-fadump.h b/arch/powerpc/platforms/pseries/rtas-fadump.h\nindex c109abf6b..65fdab7b5 100644\n--- a/arch/powerpc/platforms/pseries/rtas-fadump.h\n+++ b/arch/powerpc/platforms/pseries/rtas-fadump.h\n@@ -41,6 +41,12 @@\n #define MAX_SECTIONS\t\t\t\t10\n #define RTAS_FADUMP_MAX_BOOT_MEM_REGS\t\t7\n \n+/*\n+ * Maximum time to wait for firmware to respond to an\n+ * ibm,configure-kernel-dump RTAS call before giving up.\n+ */\n+#define RTAS_FADUMP_MAX_WAIT_MS\t\t\t60000U\n+\n /* Kernel Dump section info */\n struct rtas_fadump_section {\n \t__be32\trequest_flag;\n","prefixes":[]}