Bug 506890

Summary:	Support SIGSTKFLT and SIGSYS on linux
Product:	[Developer tools] valgrind	Reporter:	Mark Wielaard <mark>
Component:	general	Assignee:	Julian Seward <jseward>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	NOR
Version First Reported In:	3.25.0
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Bug Depends on:
Bug Blocks:	506971

Description Mark Wielaard 2025-07-10 21:33:12 UTC

The LTP kill11 testcase tries all signals.
SIGSTKFLT defaults to term and is easy to support just add something like the following to default_action in coregrind/m_signals.c

+#     if defined(VKI_SIGSTKFLT)
+      case VKI_SIGSTKFLT: /* term */
+#     endif

SIGSYS is already handled by freebsd and needs some tweaks to calculate_SKSS_from_SCSS and sync_signalhandler

Comment 1 Mark Wielaard 2025-07-11 21:40:22 UTC

This is also why the LTP waitpid01 testcase fails.

Comment 2 Mark Wielaard 2025-07-14 22:26:44 UTC

commit 969bccaaca7aab2614def013ac1f37de37fbce86
Author: Mark Wielaard <mark@klomp.org>
Date:   Tue Jul 15 00:00:44 2025 +0200

    Handle SIGSYS and SIGSTKFLT when defined
    
    Both signals were already partially handled. But calculate_SKSS_from_SCSS
    only handled SIGSYS on freebsd. default_action didn't handle SIGSTKFLT.
    And sync_signalhandler didn't expect to have to handle SIGSYS.
    
    This fixes LTP tests kill11 and waitpid01.
    
    https://bugs.kde.org/show_bug.cgi?id=506890