Re: WARNING in __do_kernel_fault
From: Will Deacon <will@kernel.org>
Date: 2021-01-27 17:19:21
Also in:
lkml
On Wed, Jan 27, 2021 at 06:00:30PM +0100, Dmitry Vyukov wrote:
On Wed, Jan 27, 2021 at 5:56 PM syzbot [off-list ref] wrote:quoted
Hello, syzbot found the following issue on: HEAD commit: 2ab38c17 mailmap: remove the "repo-abbrev" comment git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15a25264d00000 kernel config: https://syzkaller.appspot.com/x/.config?x=ad43be24faf1194c dashboard link: https://syzkaller.appspot.com/bug?extid=45b6fce29ff97069e2c5 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+45b6fce29ff97069e2c5@syzkaller.appspotmail.comThis happens on arm64 instance with mte enabled. There is a GPF in reiserfs_xattr_init on x86_64 reported: https://syzkaller.appspot.com/bug?id=8abaedbdeb32c861dc5340544284167dd0e46cde so I would assume it's just a plain NULL deref. Is this WARNING not indicative of a kernel bug? Or there is something special about this particular NULL deref?
Congratulations, you're the first person to trigger this warning! This fires if we take an unexpected data abort in the kernel but when we get into the fault handler the page-table looks ok (according to the CPU via an 'AT' instruction). Are you using QEMU system emulation? Perhaps its handling of AT isn't quite right. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel