From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 150533858415; Sat, 9 Mar 2024 16:43:36 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 150533858415 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1710002616; bh=RUNNXwneEtdvfmvdU+U6aZwWcNUtRQPVO62FeCTfY3M=; h=From:To:Subject:Date:In-Reply-To:References:From; b=iUl4mXlbH74DENl+0xO4VUBU4XsYun0myWwiyfg2obAhgoTGvoHQmM/sdEL9sgcqq /l+hPRq5MytENJ3crxc5nRltqVvAXvHuoOme9aB/muPzj9x9j9/ShKEjJ80EeqdqGW rRWtrcgnRAx930W24O2lFBKKGZ42vOu3BLOnP9MM= From: "tromey at sourceware dot org" To: gdb-prs@sourceware.org Subject: [Bug testsuite/31312] attach-many-short-lived-threads gives inconsistent results Date: Sat, 09 Mar 2024 16:43:35 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gdb X-Bugzilla-Component: testsuite X-Bugzilla-Version: HEAD X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: tromey at sourceware dot org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: cel at linux dot ibm.com X-Bugzilla-Target-Milestone: 15.1 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: 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=3D31312 --- Comment #14 from Tom Tromey --- (In reply to Carl E Love from comment #13) > There are some timing > issues that can cause the kernel to legitimately return EPERM. He pointed > me to the ptrace Linux man page Ugh :} Disappointing but what can we really do about it, I suppose. I guess if the race happens more for you, all we can conclude is that Power 10 is just too darn fast. Another possible cause for the EPERM is if > ptrace is already connected to the process. I tried to determine if this > was in fact the case. Specifically if the detach hadn't completed yet but > was not able to show that was the failure case.=20=20 Yeah, I was wondering about this as a theory for why subsequent attempts all fail. I probably distracted us a bit by ranting but IIUC this part still isn't understood. Could you maybe verify that gdb thinks it has detached all the threads it attached to? If so and the bug persists, I think we can just write it off as another kernel bug. --=20 You are receiving this mail because: You are on the CC list for the bug.=