From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793717299; b=MSU0Dt8cFZaa1CyZEzenf4jg6XfvTwKRuMjxPOcb61T6DBKNieAeMNOE8s9kHV+OShtI 3lEYQaaWi8rBuqgL51tArVcFS8AL7woIT5aCo6jc++b8ucBCbLPbPQeNx3vajEafp38ko Fps2Cxwq4+yh8Gou5MnC8vzcNRfTbDPmmPC7pUJ5Ynjd0yixGAandW6OXKIc2Wb/hyEDw SV/4qPsWwNDlmWIkQaCs/7HAlnz3OOcqlFDg7BFOMZWIEmWQK2TkYep1qucpWJaXPZ4ar bYUDN4paqGx02sWURVQ2UZpr5uZEpx6cYPrbksTeUl26dYiSrq49JrbuOdFzFvXrbHA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793717299; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=a7PYmXCvRfg0BwzdfEGz44ga4Pu8BO8P1McRUIl/QmE=; b=5ejO6e6ZyctT6IZOJswMLXzfFuiwePOurRpeuYDIE/wEvI58V0FMvyylPkGquyRtanAu aWq2/vbWbMSqbbAfUX1T+I47P9VlmPhBa+Cg0ufd1eKQucW5m3J3hAVeQaZZB3cmvi7gp VTfIBWw1jPizAMpmTyKlOrbyPd3idr3jIKvk56KigOeBYXNLWJcymhPnTStDwqK9fLq5u JDmzA9J/N1DgPlnA9ivkQplAgSHQiavTbLh64xR4NqsX9UTxfnjD8jSnoY1s56MgHPaOZ BwDJ8LdMGjbhqYcio0AckPm7oo67U9llQ0QubG2h64l3Z5SVRqAXLzsVujDJHFonw9Q== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=LYcaZ7np; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E9FF86071C15; Tue, 3 Nov 2026 14:48:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=LYcaZ7np Received: by smtp.kernel.org (Postfix) with ESMTPSA id 308B61F00919; Tue, 3 Nov 2026 14:48:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793717298; bh=a7PYmXCvRfg0BwzdfEGz44ga4Pu8BO8P1McRUIl/QmE=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=LYcaZ7npTHcFZjRzH7+Fn7MvhHCtX0Mfq+N7asGR7lT4O/D1juNNOdkQoItQPXgYp izFBnUx2NnP6oS7/UFWY3ZtlEiHQGAb8tqYNXHfwpj3k+q8UhKlx3Y4Pg97Y/XyE6C xkIjNo0WOFg/e5GUKQx1UXiaj6PoeUJ8Rmrh0A+WWO6gWPU/v7hy2cXWYqJOtZ4R1f AJe7tJP3tO80byckeYCg7WXwCIl/UiBUMp8jrZdTJOebfpv8qtOWQYXX6ex20nPx2Q aG3CJ/kyI5aKfpxI+HIjIsP6p5FlMEL6CTbtmCCpK2w8UzCSgTGpCSlE70jaIGX3Vm wS/Yy4/2pHR0Q== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RFC 25/38] powerpc/crash_dump: check ioremap_cache() in copy_oldmem_page() Reply-To: sashiko-reviews@lists.linux.dev To: "Christian Brauner" Cc: "Linus Torvalds" , "Jann Horn" , "Josef Bacik" , "Chris Mason" , "Jeff Layton" , NeilBrown , "Eric Dumazet" , "Thomas Gleixner" , "Al Viro" , "Jonathan Corbet" , "Christoph Hellwig" , "Greg Kroah-Hartman" , "Joel Granados" , "Kees Cook" , "Jan Kara" , "Jan Kara" , linux-s390@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, linux-m68k@lists.linux-m68k.org, linux-serial@vger.kernel.org, "Takashi Iwai" , linux-ext4@vger.kernel.org, "Chuck Lever" , tytso@mit.edu, "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" In-Reply-To: <20261102-work-procfs-bugfixes-v1-25-59422ed3e465@kernel.org> References: <20261102-work-procfs-bugfixes-v1-0-59422ed3e465@kernel.org> <20261102-work-procfs-bugfixes-v1-25-59422ed3e465@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 03 Nov 2026 14:48:16 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > copy_oldmem_page() maps a page of the old kernel that isn't in the > linear mapping with ioremap_cache() and copies from it without checking > whether the mapping worked. If it didn't, the copy reads from an offset > into the NULL page. That oopses unless the copy happens to be a user > copy, whose exception table entries turn the fault into a short copy. >=20 > Return -ENOMEM like the other architectures do. read_from_oldmem() > turns that into -EFAULT like any other short copy. >=20 > Reported-by: Chris Mason > Fixes: 54c32021eb6f ("[PATCH] powerpc: Add arch-dependent copy_oldmem_pag= e") > Cc: stable@vger.kernel.org > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261102-work-procf= s-bugfixes-v1-0-59422ed3e465@kernel.org?part=3D25