From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1705C28ED for ; Mon, 12 Dec 2022 13:21:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49CEBC433D2; Mon, 12 Dec 2022 13:21:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1670851286; bh=nk4+SLGDvWQ1NgDWXmKiSFthrw7paLMldJBrTj29Kv8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yTug5XJH9MG/TCbvsO23ULZblqUo1gtGobdcDJr5knUaMqBhl0Ovm7Jbuyw7u9fWz 6DoSg79/QqkMgWB37XxGKDRhvWVAoGjw95PdBmupnQF10qeUQfDHFNUBbVraeq+eId U7icz48nvUowl/f+JbvekN8KTKmMZSupGxKjxk6A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, John Starks , Saurabh Sengar , Jan Kara , Yu Zhao , Jason Gunthorpe , John Hubbard , David Hildenbrand , Dan Williams , Alistair Popple , Andrew Morton Subject: [PATCH 5.4 26/67] mm/gup: fix gup_pud_range() for dax Date: Mon, 12 Dec 2022 14:17:01 +0100 Message-Id: <20221212130918.871893386@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221212130917.599345531@linuxfoundation.org> References: <20221212130917.599345531@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: John Starks commit fcd0ccd836ffad73d98a66f6fea7b16f735ea920 upstream. For dax pud, pud_huge() returns true on x86. So the function works as long as hugetlb is configured. However, dax doesn't depend on hugetlb. Commit 414fd080d125 ("mm/gup: fix gup_pmd_range() for dax") fixed devmap-backed huge PMDs, but missed devmap-backed huge PUDs. Fix this as well. This fixes the below kernel panic: general protection fault, probably for non-canonical address 0x69e7c000cc478: 0000 [#1] SMP < snip > Call Trace: get_user_pages_fast+0x1f/0x40 iov_iter_get_pages+0xc6/0x3b0 ? mempool_alloc+0x5d/0x170 bio_iov_iter_get_pages+0x82/0x4e0 ? bvec_alloc+0x91/0xc0 ? bio_alloc_bioset+0x19a/0x2a0 blkdev_direct_IO+0x282/0x480 ? __io_complete_rw_common+0xc0/0xc0 ? filemap_range_has_page+0x82/0xc0 generic_file_direct_write+0x9d/0x1a0 ? inode_update_time+0x24/0x30 __generic_file_write_iter+0xbd/0x1e0 blkdev_write_iter+0xb4/0x150 ? io_import_iovec+0x8d/0x340 io_write+0xf9/0x300 io_issue_sqe+0x3c3/0x1d30 ? sysvec_reschedule_ipi+0x6c/0x80 __io_queue_sqe+0x33/0x240 ? fget+0x76/0xa0 io_submit_sqes+0xe6a/0x18d0 ? __fget_light+0xd1/0x100 __x64_sys_io_uring_enter+0x199/0x880 ? __context_tracking_enter+0x1f/0x70 ? irqentry_exit_to_user_mode+0x24/0x30 ? irqentry_exit+0x1d/0x30 ? __context_tracking_exit+0xe/0x70 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fc97c11a7be < snip > ---[ end trace 48b2e0e67debcaeb ]--- RIP: 0010:internal_get_user_pages_fast+0x340/0x990 < snip > Kernel panic - not syncing: Fatal exception Kernel Offset: disabled Link: https://lkml.kernel.org/r/1670392853-28252-1-git-send-email-ssengar@linux.microsoft.com Fixes: 414fd080d125 ("mm/gup: fix gup_pmd_range() for dax") Signed-off-by: John Starks Signed-off-by: Saurabh Sengar Cc: Jan Kara Cc: Yu Zhao Cc: Jason Gunthorpe Cc: John Hubbard Cc: David Hildenbrand Cc: Dan Williams Cc: Alistair Popple Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/gup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/gup.c +++ b/mm/gup.c @@ -2240,7 +2240,7 @@ static int gup_pud_range(p4d_t *p4dp, p4 next = pud_addr_end(addr, end); if (pud_none(pud)) return 0; - if (unlikely(pud_huge(pud))) { + if (unlikely(pud_huge(pud) || pud_devmap(pud))) { if (!gup_huge_pud(pud, pudp, addr, next, flags, pages, nr)) return 0;