Your message dated Mon, 17 Apr 2023 01:55:46 +0200 with message-id <[email protected]> and subject line kde-workspace has been superseded by Plasma 5 has caused the Debian Bug report #843822, regarding KDE binaries (ksplashqml) *silently* fail if they cannot allocate memory, causing a hang at startup to be marked as done.
This means that you claim that the problem has been dealt with. If this is not the case it is now your responsibility to reopen the Bug report if necessary, and/or fix the problem forthwith. (NB: If you are a system administrator and have no idea what this message is talking about, this may indicate a serious mail system misconfiguration somewhere. Please contact [email protected] immediately.) -- 843822: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=843822 Debian Bug Tracking System Contact [email protected] with problems
--- Begin Message ---Package: kde-workspace-bin Version: 4:4.11.13-2 When attempting to start kde with a too low ulimit -d applied, kde just hangs, without displaying its splash screen, nor popping up any error dialog, nor printing any error message to stderr (.xsession-errors) This makes diagnosing such situations needlessly difficult. strace shows the following sequence: 6907 execve("/usr/bin/ksplashqml", ["ksplashqml", "lines", "--pid"], [/* 59 vars */]) = 0 ... 6907 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f8ada54aa50) = 6908 ... 6907 exit_group(0) = ? 6907 +++ exited with 0 +++ ... 6908 mmap(NULL, 2147483648, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE, -1, 0 <unfinished ...> 6908 <... mmap resumed> ) = -1 ENOMEM (Cannot allocate memory) 6908 --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0xbbadbeef} --- 6908 +++ killed by SIGSEGV +++ This shows several problems: 1. No attempt is made by the victim process (ksplashqml) to write an error message to stderr 2. Apparently the victim process tries to use the pointer returned by mmap without first checking it for MAP_FAILED, which results in a segfault. 3. The process is started with a double-fork making it impossible for the parent process to react to the SEGV either. Double fork is a weird way of starting a child process that is meant to be shortlived (such as the splash screen) This situation may seem cosmetical (it's the splash screen, after all...) but unfortunately it occurs similarly for /usr/bin/kbuildsycoca4 --incremental --checkstamps and /usr/bin/kdeinit4 --oom-pipe +kcminit_startup Occasionally the following message is indeed printed to stderr: QThread::start: Thread creation error: Resource temporarily unavailable This is still misleading, as it doesn't tell *which* resource. Indeed, the error from the kernel is ENOMEM, and not EAGAIN. This makes it needlessly difficult to debug such a situation. A memory issue is really not expected on a hang (rather than on a crash...) Thanks for fixing this. Alain
--- End Message ---
--- Begin Message ---Version: 4:4.11.22-3+rm src:kde-workspace was last released with Debian 8 (jessie) in April 2015 and was removed from the Debian archive afterwards. It has been superseded by Plasma 5. See https://bugs.debian.org/803635 for details on the removal. I'm closing the remaining bug reports now. Andreas
--- End Message ---
