Date: Sat, 13 Feb 2021 18:23:53 +0000 From: bugzilla-noreply@freebsd.org To: emulation@FreeBSD.org Subject: [Bug 253337] Linuxulator: glibc's pthread_getattr_np reports stack size as 124K Message-ID: <bug-253337-4077-a4IEErlgoj@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-253337-4077@https.bugs.freebsd.org/bugzilla/> References: <bug-253337-4077@https.bugs.freebsd.org/bugzilla/>
next in thread | previous in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D253337 --- Comment #10 from Alex S <iwtcex@gmail.com> --- (In reply to Conrad Meyer from comment #8) I noticed neither Linux nor FreeBSD actually bothers with accurate stack mappings in /proc/self/map. About multiple threads Linux's documentation plainly states "[stack:<tid>] (from Linux 3.4 to 4.4) =E2=80= =A6 This field was removed in Linux 4.5, since providing this information for a process with large numbers of threads is expensive." However, this looks a bit fishy even with a basic single-threaded test: xubuntu@xubuntu:~$ cat address.c=20 #define _GNU_SOURCE #include <assert.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> int main() { int i =3D 1; fprintf(stderr, "[[%p]]\n", &i); system("cat /proc/self/maps | tail -n 5"); return 0; } xubuntu@xubuntu:~$ gcc address.c -o test xubuntu@xubuntu:~$ ./test [[0x7ffe7a0cbca4]] 7f4f3c7af000-7f4f3c7b0000 rw-p 00000000 00:00 0=20 7ffe37e2e000-7ffe37e4f000 rw-p 00000000 00:00 0=20=20=20=20=20=20=20=20=20= =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20 [stack] 7ffe37fd0000-7ffe37fd3000 r--p 00000000 00:00 0 [v= var] 7ffe37fd3000-7ffe37fd4000 r-xp 00000000 00:00 0 [v= dso] ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0=20=20=20=20=20=20= =20=20=20=20=20=20=20=20=20=20=20 [vsyscall] I mean, 0x7ffe7a0cbca4 is right between [vdso] and [vsyscall]. Since apparently we are already in the pure fantasy land, it's probably not a big deal to mess this a bit more. --=20 You are receiving this mail because: You are the assignee for the bug.=
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-253337-4077-a4IEErlgoj>