From patchwork Sat Feb 11 09:13:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Asahi Lina X-Patchwork-Id: 13136983 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C0B38C636CC for ; Sat, 11 Feb 2023 09:14:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=tJ5ADrATM+vXc5bsRBVDIqZ8VGgqYD1Fhf5MnldC16s=; b=aXY3aepaNxWhik mlKq56M+7E+FnGTmjVspeIq8yrRRQ7exyggYdjjkCpn9enE+GNAe+ouFB14mUd4UXj9chY25Eai3B INxF0UYlzqiYndO7VE2plAz6pGURie28bAtIKh1hJF17+JQ3qOgyse/Shbt2YYF54/oJR7Wc7cX9G dylZriphtR73RdhNJFYQeqxuI8kGrq5mAnNk0RV+yvRENuLkwymonePsDOYFmdDo0xHwewyUF3bZq j7GivQ9r/9goOMFZLS93JlTf8Ey27Cx3SObRnVr0Ohb0nzRAPshCg6NDNfQvypKLqU9glyLz8c6yP bQNqxeIjGdgeCImaCFYw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pQlx0-0096o5-Td; Sat, 11 Feb 2023 09:13:43 +0000 Received: from marcansoft.com ([212.63.210.85] helo=mail.marcansoft.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pQlww-0096nP-Oa for linux-arm-kernel@lists.infradead.org; Sat, 11 Feb 2023 09:13:40 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: linasend@asahilina.net) by mail.marcansoft.com (Postfix) with ESMTPSA id 38358424EC; Sat, 11 Feb 2023 09:13:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=asahilina.net; s=default; t=1676106812; bh=I+IK6qQ7gaXsQ1ViBTeWacu6GcpTW5fOOPr4of64kW4=; h=From:To:Cc:Subject:Date; b=PHMlETyumw5IcWqF65/BEQxoJJeVVwLmWGdfxAfFyvIU5qlDaYyQj49KuXHR8RLbB JW0bMrm5Z1kmjY7woj6LHCj0cbTwGkDsluhhLXYRo9cl1hgXM02VRJsoValgx4tepJ 1Kpi1WTVux6WNEo2g5dW6rLIZt/IHGdCb/FOIxAheGoDcJj4/IeXrnQ0H0JFcrib/w 6iKiLvH7i9l9ekTjMrnAo14cuxX12Cww2m8tuJUqkWpXrmttcCaJKmh3nPSUdfpsUB 5qurZz4FqzaiyCtNtpBw0YsTKP6JKtWDRux7CbimErCKVKYrwp9EZ+XDSvetcoZpq2 hCm5mHLiTb2Ng== From: Asahi Lina To: Arnd Bergmann , Hector Martin , Sven Peter Cc: Alyssa Rosenzweig , asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Asahi Lina Subject: [PATCH] soc: apple: rtkit: Do not copy the reg state structure to the stack Date: Sat, 11 Feb 2023 18:13:02 +0900 Message-Id: <20230211091302.4576-1-lina@asahilina.net> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230211_011339_286139_28C4A5C8 X-CRM114-Status: GOOD ( 12.73 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The register state struct is 848 bytes, which ends up bloating the apple_rtkit_crashlog_dump_regs stack frame beyond 1024 on some 32-bit platforms, triggering compile warnings. This doesn't matter for 64BIT/ARM64, but there's also no good reason to copy the structure to the stack in this case. We can use __packed to avoid alignment issues, there are no double-read hazards, and this is a fatal error path so performance does not matter. Fixes: 22991d8d5725 ("soc: apple: rtkit: Add register dump decoding to crashlog") Signed-off-by: Asahi Lina Reviewed-by: Eric Curtin --- drivers/soc/apple/rtkit-crashlog.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/soc/apple/rtkit-crashlog.c b/drivers/soc/apple/rtkit-crashlog.c index dfa74b32eda2..8319e365110b 100644 --- a/drivers/soc/apple/rtkit-crashlog.c +++ b/drivers/soc/apple/rtkit-crashlog.c @@ -57,7 +57,7 @@ struct apple_rtkit_crashlog_regs { u64 unk_X; u64 esr; u64 unk_Z; -}; +} __packed; static_assert(sizeof(struct apple_rtkit_crashlog_regs) == 0x350); static void apple_rtkit_crashlog_dump_str(struct apple_rtkit *rtk, u8 *bfr, @@ -126,18 +126,18 @@ static void apple_rtkit_crashlog_dump_mailbox(struct apple_rtkit *rtk, u8 *bfr, static void apple_rtkit_crashlog_dump_regs(struct apple_rtkit *rtk, u8 *bfr, size_t size) { - struct apple_rtkit_crashlog_regs regs; + struct apple_rtkit_crashlog_regs *regs; const char *el; int i; - if (size < sizeof(regs)) { + if (size < sizeof(*regs)) { dev_warn(rtk->dev, "RTKit: Regs section too small: 0x%zx", size); return; } - memcpy(®s, bfr, sizeof(regs)); + regs = (struct apple_rtkit_crashlog_regs *)bfr; - switch (regs.psr & PSR_MODE_MASK) { + switch (regs->psr & PSR_MODE_MASK) { case PSR_MODE_EL0t: el = "EL0t"; break; @@ -160,11 +160,11 @@ static void apple_rtkit_crashlog_dump_regs(struct apple_rtkit *rtk, u8 *bfr, dev_warn(rtk->dev, "RTKit: Exception dump:"); dev_warn(rtk->dev, " == Exception taken from %s ==", el); - dev_warn(rtk->dev, " PSR = 0x%llx", regs.psr); - dev_warn(rtk->dev, " PC = 0x%llx\n", regs.pc); - dev_warn(rtk->dev, " ESR = 0x%llx\n", regs.esr); - dev_warn(rtk->dev, " FAR = 0x%llx\n", regs.far); - dev_warn(rtk->dev, " SP = 0x%llx\n", regs.sp); + dev_warn(rtk->dev, " PSR = 0x%llx", regs->psr); + dev_warn(rtk->dev, " PC = 0x%llx\n", regs->pc); + dev_warn(rtk->dev, " ESR = 0x%llx\n", regs->esr); + dev_warn(rtk->dev, " FAR = 0x%llx\n", regs->far); + dev_warn(rtk->dev, " SP = 0x%llx\n", regs->sp); dev_warn(rtk->dev, "\n"); for (i = 0; i < 31; i += 4) { @@ -172,12 +172,12 @@ static void apple_rtkit_crashlog_dump_regs(struct apple_rtkit *rtk, u8 *bfr, dev_warn(rtk->dev, " x%02d-x%02d = %016llx %016llx %016llx %016llx\n", i, i + 3, - regs.regs[i], regs.regs[i + 1], - regs.regs[i + 2], regs.regs[i + 3]); + regs->regs[i], regs->regs[i + 1], + regs->regs[i + 2], regs->regs[i + 3]); else dev_warn(rtk->dev, " x%02d-x%02d = %016llx %016llx %016llx\n", i, i + 3, - regs.regs[i], regs.regs[i + 1], regs.regs[i + 2]); + regs->regs[i], regs->regs[i + 1], regs->regs[i + 2]); } dev_warn(rtk->dev, "\n");