From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id C1B7C3857B86; Fri, 16 Feb 2024 18:52:01 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org C1B7C3857B86 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1708109521; bh=9zHqD+CYGWJZ/tPUYJR2x1hLy5QAH+HbrsaU0Ex3yto=; h=From:To:Subject:Date:In-Reply-To:References:From; b=tv2bncSWv76HP//PQvzuHXVLp1WDFu/qe4nVavyccvQZkxmfU4eHXaXUiysAyeM4B 3Qm7H0PK4pQnlDV/pn3YwbNFrZR9YBlJyWLYQ1a/2bN+9Mc8zbt+2Cjggb6MqDN96J rUUgTemGMy7y1Q2YS9rtnRKmIhCU248hubUTwKQI= From: "sourceware-bugzilla at mkarcher dot dialup.fu-berlin.de" To: glibc-bugs@sourceware.org Subject: [Bug libc/31394] clone on sparc might fail with -EFAULT for no valid reason Date: Fri, 16 Feb 2024 18:52:01 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: libc X-Bugzilla-Version: 2.38 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: sourceware-bugzilla at mkarcher dot dialup.fu-berlin.de X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: attachments.created Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D31394 --- Comment #1 from Michael Karcher --- Created attachment 15374 --> https://sourceware.org/bugzilla/attachment.cgi?id=3D15374&action=3Ded= it patch to mitigate the kernel issue The issue has been obversed on a very wide range of kernel and glibc versio= ns, e.g. on Debian wheezy (Linux 3.2.0 / glibc 2.13), but also on current gentoo machines (Linux 6.1 / glibc 2.38-r9). I developed a patch that causes the stack to be in a state that makes the system call clone work reliably, by first invoking flushw from userspace be= fore entering the kernel. I believe the underlying issue is the way the kernel handles page faults during flushw ("The user stack is bolixed"), so I chose this way of pre-faulting the required pages. --=20 You are receiving this mail because: You are on the CC list for the bug.=