Date: Fri, 30 Oct 2020 00:00:07 +0100 From: Milan P. Stanić <mps@...anta.net> To: musl@...ts.openwall.com Subject: Re: [PATCH v2] MT fork On Thu, 2020-10-29 at 23:21, Szabolcs Nagy wrote: > * Milan P. Stanić <mps@...anta.net> [2020-10-29 21:55:41 +0100]: > > On Thu, 2020-10-29 at 17:13, Szabolcs Nagy wrote: > > > * Milan P. Stanić <mps@...anta.net> [2020-10-29 00:06:10 +0100]: > > > > > > > > Applied this patch on top of current musl master, build it on Alpine and > > > > installed. > > > > > > > > Tested by building ruby lang. Works fine. > > > > Also tested building zig lang, works fine. > > > > But crystal lang builds fine, but running it hangs. strace shows: > > > > ------------- > > > > [pid 5573] futex(0x7efc50fba9e4, FUTEX_WAIT_PRIVATE, 2, NULL <unfinished ...> > > > > [pid 5568] futex(0x7efc5118f984, FUTEX_REQUEUE_PRIVATE, 0, 1, 0x7efc514b67a4) = 1 > > > > [pid 5568] futex(0x7efc514b67a4, FUTEX_WAKE_PRIVATE, 1) = 1 > > > > [pid 5571] <... futex resumed>) = 0 > > > > [pid 5568] futex(0x7efc511099e4, FUTEX_WAIT_PRIVATE, 2, NULL <unfinished ...> > > > > [pid 5571] futex(0x7efc510409e4, FUTEX_WAIT_PRIVATE, 2, NULL > > > > ------------- > > > > where it hangs. > > > > > > try to attach gdb to the process that hang and do > > > > > > thread apply all bt > > > > > > (make sure musl-dbg is installed) > > > > I cannot attach gdb for running process because my Alpine development > > boxes are lxc containers where CAP_SYS_PTRACE is not enabled afaik. > > there should be a way to config lxc to allow ptrace. > > > I installed musl-dbg and run program with 'gdb .build/crystal' and result is: > > ---------- > > Reading symbols from .build/crystal... > > (gdb) run > > Starting program: /home/mps/aports/community/crystal/src/crystal-0.35.1/.build/crystal > > > > Program received signal SIGSEGV, Segmentation fault. > > hm segfault is not a hang.. > > libgc tries to find stack bounds by registering a segfault handler > and walking stack pages until it triggers. > > gdb stops at signals, this one is harmless, you should just continue > until you see a hang, then interrupt and bt. I did continue now and stopped it when it hangs. Attached is gdb log produced by 'thread apply all bt' > > 0x00007ffff401c463 in GC_find_limit_with_bound () from /usr/lib/libgc.so.1 > > (gdb) bt > > #0 0x00007ffff401c463 in GC_find_limit_with_bound () from /usr/lib/libgc.so.1 > > #1 0x00007ffff401c522 in GC_init_linux_data_start () from /usr/lib/libgc.so.1 > > #2 0x00007ffff401b2e0 in GC_init () from /usr/lib/libgc.so.1 > > #3 0x00005555555668d8 in init () at > > /home/mps/aports/community/crystal/src/crystal-0.35.1/src/gc/boehm.cr:127 > > #4 main () at /home/mps/aports/community/crystal/src/crystal-0.35.1/src/crystal/main.cr:35 > > #5 main () at /home/mps/aports/community/crystal/src/crystal-0.35.1/src/crystal/main.cr:114 > > (gdb) > > ---------- > > > > Same with 'thread apply all bt'. > > > > gc lib (garbage collector, https://hboehm.info/gc/) version is > > gc-dev-8.0.4-r1 on Alpine. > > > > I can't test this on native machine because currently I don't have any > > x86_64 with enough resources to build crystal. On aarch64 it even can't > > be built with mt-fork patch, hangs always during build. > > > > -- > > Regards Download attachment "gdb.txt.gz" of type "application/gzip" (1322 bytes)
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.