From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 12035CAC5A7 for ; Mon, 22 Sep 2025 10:18:00 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1v0dbD-0001fT-FQ; Mon, 22 Sep 2025 06:16:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1v0daw-0001f0-W8 for qemu-devel@nongnu.org; Mon, 22 Sep 2025 06:16:33 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1v0daj-0008Lk-HA for qemu-devel@nongnu.org; Mon, 22 Sep 2025 06:16:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1758536169; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XYvRW8l4NMlNeBru1cTxqd+PHgWLQfAyd3NAbUjWJlw=; b=CtWNzrxMVi0Bu3/M6ImQUwc4let3plC/g2V7Sfr3gHQIqhKtIbW8jmvJUYfvr2BwbhAcb1 hrHm9c9HQ6+aHUSXvKkfqVtA/rG9+ODuD4VyaykuiFijffUmHjaUz0HWJo976KQgme35dy aX5dL3XNsMbR/o5YrC7UOUqVRLGuwAA= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-636-ynB_cotdNO--fakQAeR5Ow-1; Mon, 22 Sep 2025 06:16:00 -0400 X-MC-Unique: ynB_cotdNO--fakQAeR5Ow-1 X-Mimecast-MFC-AGG-ID: ynB_cotdNO--fakQAeR5Ow_1758536159 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 0509119560B2; Mon, 22 Sep 2025 10:15:59 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.69]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 866453000198; Mon, 22 Sep 2025 10:15:56 +0000 (UTC) Date: Mon, 22 Sep 2025 11:15:52 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Julian Ganz Cc: Alex =?utf-8?Q?Benn=C3=A9e?= , qemu-devel@nongnu.org, Pierrick Bouvier , Alexandre Iooss , Mahmoud Mandour Subject: Re: [PATCH v6 23/25] tests: add plugin asserting correctness of discon event's to_pc Message-ID: References: <073cad7dd8ae509ff64a2835fd146833b60c1f60.1757018626.git.neither@nut.email> <87segf69f6.fsf@draig.linaro.org> <51342318ee32c932dc2a867c808989ea627d874f@nut.email> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <51342318ee32c932dc2a867c808989ea627d874f@nut.email> User-Agent: Mutt/2.2.14 (2025-02-20) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.442, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, T_SPF_TEMPERROR=0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Sep 22, 2025 at 10:11:23AM +0000, Julian Ganz wrote: > Hi Alex, > > September 21, 2025 at 6:46 PM, "Alex BennΓ©e" wrote: > > Julian Ganz writes: > > > +static void report_mismatch(const char *pc_name, unsigned int vcpu_index, > > > + enum qemu_plugin_discon_type type, uint64_t last, > > > + uint64_t expected, uint64_t encountered) > > > +{ > > > + GString *report; > > > > > This could be: > > > > g_autoptr(GString) buf = g_string_new(NULL); > > I wanted to avoid doing an allocation regardless of whether we do have > anything to report or not. But I guess a performance plugin isn't > performance critical enough to worry? Anyway, I will have another look > at g_autoptr. IMHO the use of GString is pointless, there is only a single g_string_append_printf call. GString is only useful when incrementally constructing a string from many pieces. This code could have just used 'g_strdup_printf' AFAICT. > > > > + const char *discon_type_name = "unknown"; > > > + > > > + if (addr_eq(expected, encountered)) { > > > + return; > > > + } > > > + > > > + switch (type) { > > > + case QEMU_PLUGIN_DISCON_INTERRUPT: > > > + discon_type_name = "interrupt"; > > > + break; > > > + case QEMU_PLUGIN_DISCON_EXCEPTION: > > > + discon_type_name = "exception"; > > > + break; > > > + case QEMU_PLUGIN_DISCON_HOSTCALL: > > > + discon_type_name = "hostcall"; > > > + break; > > > + default: > > > + break; > > > + } > > > + > > > + report = g_string_new(NULL); > > > + g_string_append_printf(report, > > > + "Discon %s PC mismatch on VCPU %d\nExpected: %" > > > + PRIx64"\nEncountered: %"PRIx64"\nExecuted Last: %" > > > + PRIx64"\nEvent type: %s\n", > > > + pc_name, vcpu_index, expected, encountered, last, > > > + discon_type_name); > > > + qemu_plugin_outs(report->str); > > > > > I think we might want to flush here because > > Yes we do. I probably (incorrectly) assumed `qemu_plugin_outs` already > did that. > > > > > > > > > + if (abort_on_mismatch) { > > > + g_abort(); > > > + } > > > > > This is firing on: > > > > πŸ•™17:35:50 alex@draig:tests/tcg/i386-linux-user on ξ‚  review/tcg-discon-v6 [$!?] > > ➜ make run-plugin-catch-syscalls-with-libdiscons.so V=1 > > timeout -s KILL --foreground 120 env QEMU=/home/alex/lsrc/qemu.git/builds/sanitisers/qemu-i386 /home/alex/lsrc/qemu.git/builds/sanitisers/qemu-i386 -plugin ../plugins/libdiscons.so -d plugin -D catch-syscalls-with-libdiscons.so.pout catch-syscalls > run-plugin-catch-syscalls-with-libdiscons.so.out > > Aborted > > make: *** [Makefile:226: run-plugin-catch-syscalls-with-libdiscons.so] Error 134 > > πŸ•™17:35:52 alex@draig:tests/tcg/i386-linux-user on ξ‚  review/tcg-discon-v6 [$!?] [πŸ”΄ USAGE] > > βœ— > > > > although it never gets to the point of reporting what failed: > > > > Thread 1 "qemu-i386" hit Breakpoint 1, __GI_abort () at ./stdlib/abort.c:72 > > warning: 72 ./stdlib/abort.c: No such file or directory > > (gdb) bt > > #0 __GI_abort () at ./stdlib/abort.c:72 > > #1 0x00007ffff630874d in report_mismatch (pc_name=0x7ffff630a220 "target", vcpu_index=0, type=QEMU_PLUGIN_DISCON_EXCEPTION, last=134574955, expected=134574953, > > encountered=134574955) at ../../tests/tcg/plugins/discons.c:89 > > #2 0x00007ffff6308c0d in insn_exec (vcpu_index=0, userdata=0x0) at ../../tests/tcg/plugins/discons.c:132 > > #3 0x00007fffea431114 in code_gen_buffer () > > #4 0x000055555577b0a6 in cpu_tb_exec (cpu=0x529000005200, itb=0x7fffea431000 , tb_exit=0x7ffff49c9530) at ../../accel/tcg/cpu-exec.c:438 > > #5 0x000055555577c92f in cpu_loop_exec_tb (cpu=0x529000005200, tb=0x7fffea431000 , pc=134574955, last_tb=0x7ffff49c9540, tb_exit=0x7ffff49c9530) > > at ../../accel/tcg/cpu-exec.c:871 > > #6 0x000055555577d151 in cpu_exec_loop (cpu=0x529000005200, sc=0x7ffff483a740) at ../../accel/tcg/cpu-exec.c:981 > > #7 0x000055555577d2fe in cpu_exec_setjmp (cpu=0x529000005200, sc=0x7ffff483a740) at ../../accel/tcg/cpu-exec.c:998 > > #8 0x000055555577d4c8 in cpu_exec (cpu=0x529000005200) at ../../accel/tcg/cpu-exec.c:1024 > > #9 0x00005555557bfc83 in cpu_loop (env=0x529000007dd0) at ../../linux-user/i386/cpu_loop.c:215 > > #10 0x00005555558ee3e1 in main (argc=4, argv=0x7fffffffe688, envp=0x7fffffffe6b0) at ../../linux-user/main.c:1038 > > (gdb) f 1 > > #1 0x00007ffff630874d in report_mismatch (pc_name=0x7ffff630a220 "target", vcpu_index=0, type=QEMU_PLUGIN_DISCON_EXCEPTION, last=134574955, expected=134574953, > > encountered=134574955) at ../../tests/tcg/plugins/discons.c:89 > > 89 g_abort(); > > (gdb) p report > > $1 = (GString *) 0x50300002bf00 > > (gdb) p report->Str > > There is no member named Str. > > (gdb) p report->str > > $2 = (gchar *) 0x51100001fbc0 "Discon target PC mismatch on VCPU 0\nExpected: 8057369\nEncountered: 805736b\nExecuted Last: 805736b\nEvent type: exception\n" > > (gdb) > > > > I think this is where it is going wrong: > > > > IN: _dl_early_allocate > > 0x0805736b: 89 c2 movl %eax, %edx > > 0x0805736d: 8d 1c 28 leal (%eax, %ebp), %ebx > > 0x08057370: 89 c8 movl %ecx, %eax > > 0x08057372: cd 80 int $0x80 > > Thanks! I'll have a closer look. > > > > > > > + g_string_free(report, true); > > > > > so we could drop this... or.. > > As aborting is optional, we should free. > > Regards, > Julian > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|