From nobody Sun Dec 14 17:58:56 2025 Received: from mail-24418.protonmail.ch (mail-24418.protonmail.ch [109.224.244.18]) (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 B26F635A922 for ; Wed, 29 Oct 2025 20:10:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=109.224.244.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761768638; cv=none; b=IZEHdqgMO8RO+Vk2RBdHSrH8Gpy2zLEM9vd3mU29zuicGGxI9172IoMrxIUb+2xHKNX7oqdXDAc7Fkie9+Rob4FLcBbC4jttnDk/EjyMjE52gZ12BbIGes9OL9a3Sj7QGPjnTCPliwohkebAy7SkK4HbpHriJ7TqA1TxGBTM80g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761768638; c=relaxed/simple; bh=S2a1Kw0sC3CsXwE/Uet1J3QooijcrYchVxhPMvMQoO4=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=YUhElqtpZ6dyVUI7ONuzp31WBT6K0464MWQi4Sv8b4QviOXXstRINjl/6cWQLuuVYsbCz86F2u4Qm6eCxiuTDu207MouAtINLtu2QoCiOySe7ilkYc7eV887+aPCufg9Cr67Gfgzfd8adbOJXUYPchnTGxvGlrIvQS2OBfQCvNc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me; spf=pass smtp.mailfrom=pm.me; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b=IAf8Yf83; arc=none smtp.client-ip=109.224.244.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pm.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b="IAf8Yf83" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail3; t=1761768631; x=1762027831; bh=S2a1Kw0sC3CsXwE/Uet1J3QooijcrYchVxhPMvMQoO4=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=IAf8Yf83jJpokLTSbKrc6oZO27DAaw7BQUnE7WCUryg0gLluEitf1I28vmC/H7oml bjw+r/ilmQ+FUR4ZrZ/gaUrnBytCchvTJWpL3VZOkGgYjmYKURcbqbQHdnYxCYWLeN 9re+mOvg0PqgLR5FpUhW6rfiKnYi8Ry2ssLz3XCsOgvkpInMaxWEe+dOpc18CRsWgk 4N4hCGNQG4AJ6xEXdQIaI+pniq8mMD2ntUxxe+DxtFOWAvmeACobKS5Nqb1DTw+C6x xOus8MYRr0WlJflGSWspRnnlWmjeV4ZsSgXO8DpPRXLVZTHll8Qu+wV7nOCuGbYgBC QQZoRZPiCqMqQ== Date: Wed, 29 Oct 2025 20:10:26 +0000 To: xin@zytor.com, peterz@infradead.org, kaleshsingh@google.com, kbingham@kernel.org, akpm@linux-foundation.org, nathan@kernel.org, ryabinin.a.a@gmail.com, dave.hansen@linux.intel.com, bp@alien8.de, morbo@google.com, jeremy.linton@arm.com, smostafa@google.com, kees@kernel.org, baohua@kernel.org, vbabka@suse.cz, justinstitt@google.com, wangkefeng.wang@huawei.com, leitao@debian.org, jan.kiszka@siemens.com, fujita.tomonori@gmail.com, hpa@zytor.com, urezki@gmail.com, ubizjak@gmail.com, ada.coupriediaz@arm.com, nick.desaulniers+lkml@gmail.com, ojeda@kernel.org, brgerst@gmail.com, elver@google.com, pankaj.gupta@amd.com, glider@google.com, mark.rutland@arm.com, trintaeoitogc@gmail.com, jpoimboe@kernel.org, thuth@redhat.com, pasha.tatashin@soleen.com, dvyukov@google.com, jhubbard@nvidia.com, catalin.marinas@arm.com, yeoreum.yun@arm.com, mhocko@suse.com, lorenzo.stoakes@oracle.com, samuel.holland@sifive.com, vincenzo.frascino@arm.com, bigeasy@linutronix.de, surenb@google.com, ardb@kernel.org, Liam.Howlett@oracle.com, nicolas.schier@linux.dev, ziy@nvidia.com, kas@kernel.org, tglx@linutronix.de, mingo@redhat.com, broonie@kernel.org, corbet@lwn.net, andreyknvl@gmail.com, maciej.wieczor-retman@intel.com, david@redhat.com, maz@kernel.org, rppt@kernel.org, will@kernel.org, luto@kernel.org From: Maciej Wieczor-Retman Cc: kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-kbuild@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, linux-doc@vger.kernel.org, m.wieczorretman@pm.me Subject: [PATCH v6 16/18] arm64: Unify software tag-based KASAN inline recovery path Message-ID: <0a21096d806eafa679798b9844ec33bf8a5499a4.1761763681.git.m.wieczorretman@pm.me> In-Reply-To: References: Feedback-ID: 164464600:user:proton X-Pm-Message-ID: ab91b91b5b8eb35edef4ae212700531bcd4f5e1b Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Maciej Wieczor-Retman To avoid having a copy of a long comment explaining the intricacies of the inline KASAN recovery system and issues for every architecture that uses the software tag-based mode, a unified kasan_die_unless_recover() function was added. Use kasan_die_unless_recover() in the kasan brk handler to cleanup the long comment, that's kept in the non-arch KASAN code. Signed-off-by: Maciej Wieczor-Retman Acked-by: Catalin Marinas Acked-by: Alexander Potapenko --- Changelog v6: - Add Catalin's Acked-by tag. Changelog v5: - Split arm64 portion of patch 13/18 into this one. (Peter Zijlstra) arch/arm64/kernel/traps.c | 17 +---------------- 1 file changed, 1 insertion(+), 16 deletions(-) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 681939ef5d16..b1efc11c3b5a 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -1071,22 +1071,7 @@ int kasan_brk_handler(struct pt_regs *regs, unsigned= long esr) =20 kasan_report(addr, size, write, pc); =20 - /* - * The instrumentation allows to control whether we can proceed after - * a crash was detected. This is done by passing the -recover flag to - * the compiler. Disabling recovery allows to generate more compact - * code. - * - * Unfortunately disabling recovery doesn't work for the kernel right - * now. KASAN reporting is disabled in some contexts (for example when - * the allocator accesses slab object metadata; this is controlled by - * current->kasan_depth). All these accesses are detected by the tool, - * even though the reports for them are not printed. - * - * This is something that might be fixed at some point in the future. - */ - if (!recover) - die("Oops - KASAN", regs, esr); + kasan_die_unless_recover(recover, "Oops - KASAN", regs, esr, die); =20 /* If thread survives, skip over the brk instruction and continue: */ arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE); --=20 2.51.0