Re: make run_tests -C proc: proc-pid-vm assertion failed.

[Zhou, Jie2X]

hi,

>Can't reproduce. Please, post "strace -f ./proc-pid-vm".
test in "Debian GNU/Linux bookworm/sid"
And the strace output is attached.

best regards,

________________________________________
From: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Sent: Friday, September 9, 2022 1:20 PM
To: Zhou, Jie2X
Cc: shuah@xxxxxxxxxx; guozhengkui@xxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; linux-kselftest@xxxxxxxxxxxxxxx; Li, Philip
Subject: Re: make run_tests -C proc: proc-pid-vm assertion failed.

On Fri, Sep 09, 2022 at 10:19:16AM +0800, Jie2x Zhou wrote:
> hi,
>
> The test error is caused by g_vsyscall set failed.


> Error output:
>  selftests: proc: proc-pid-vm
>  proc-pid-vm: proc-pid-vm.c:389: main: Assertion `rv == len' failed.
>  Aborted
>
> g_vsyscall is set to 0.
> In proc-pid-vm.c:
> /*
>  * 0: vsyscall VMA doesn't exist        vsyscall=none
>  * 1: vsyscall VMA is r-xp              vsyscall=emulate
>  * 2: vsyscall VMA is --xp              vsyscall=xonly
>  */
> static int g_vsyscall;
> static const char *str_vsyscall;
>
> static const char str_vsyscall_0[] = "";
> static const char str_vsyscall_1[] =
> "ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]\n";
> static const char str_vsyscall_2[] =
> "ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]\n";
>
> The /proc/%u/maps output is:
> buf=100000000-100001000 r-xp 00000000 00:2d 2                                /tmp/#2 (deleted)
> ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]
>
> So the g_vsyscall should be 2 according to commentary(2: vsyscall VMA is --xp).
> Is it a bug?

Can't reproduce. Please, post "strace -f ./proc-pid-vm".
execve("./proc-pid-vm", ["./proc-pid-vm"], 0x7ffe5aee08c8 /* 111 vars */) = 0
brk(NULL)                               = 0x55cafcf35000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f48d79c3000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=29295, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 29295, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f48d79bb000
close(3)                                = 0
openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\300\223\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
pread64(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\200\0\300\4\0\0\0\1\0\0\0\0\0\0\0", 32, 848) = 32
pread64(3, "\4\0\0\0\24\0\0\0\3\0\0\0GNU\0\335~7a\231\333\307\256\207\267%F\271\34\267\211"..., 68, 880) = 68
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=2049032, ...}, AT_EMPTY_PATH) = 0
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
mmap(NULL, 2101136, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f48d77ba000
mmap(0x7f48d77e2000, 1499136, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x28000) = 0x7f48d77e2000
mmap(0x7f48d7950000, 360448, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x196000) = 0x7f48d7950000
mmap(0x7f48d79a8000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1ed000) = 0x7f48d79a8000
mmap(0x7f48d79ae000, 53136, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f48d79ae000
close(3)                                = 0
mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f48d77b7000
arch_prctl(ARCH_SET_FS, 0x7f48d77b7740) = 0
set_tid_address(0x7f48d77b7a10)         = 10678
set_robust_list(0x7f48d77b7a20, 24)     = 0
mprotect(0x7f48d79a8000, 16384, PROT_READ) = 0
mprotect(0x55cafc70a000, 4096, PROT_READ) = 0
mprotect(0x7f48d79f5000, 8192, PROT_READ) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
munmap(0x7f48d79bb000, 29295)           = 0
clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f48d77b7a10) = 10679
strace: Process 10679 attached
[pid 10678] wait4(10679,  <unfinished ...>
[pid 10679] set_robust_list(0x7f48d77b7a20, 24) = 0
[pid 10679] prlimit64(0, RLIMIT_CORE, {rlim_cur=0, rlim_max=0}, NULL) = 0
[pid 10679] rt_sigaction(SIGSEGV, {sa_handler=0x55cafc708080, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f48d77f7af0}, NULL, 8) = 0
[pid 10679] --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x55cafbd06000} ---
[pid 10679] exit_group(1)               = ?
[pid 10679] +++ exited with 1 +++
<... wait4 resumed>[{WIFEXITED(s) && WEXITSTATUS(s) == 1}], 0, NULL) = 10679
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=10679, si_uid=0, si_status=1, si_utime=0, si_stime=0} ---
unshare(CLONE_NEWNS)                    = 0
mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) = 0
mount(NULL, "/tmp", "tmpfs", 0, NULL)   = 0
close(0)                                = 0
openat(AT_FDCWD, "/", O_RDONLY|O_PATH|O_DIRECTORY) = 0
openat(AT_FDCWD, "/tmp", O_WRONLY|O_EXCL|O_TMPFILE, 0700) = 3
writev(3, [{iov_base="\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\2\0>\0\1\0\0\0x\0\0\0\1\0\0\0"..., iov_len=64}, {iov_base="\1\0\0\0\5\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1\0\0\0\0\0\0\0\0\0\0\0"..., iov_len=56}, {iov_base="H\277\0\20\0\0\1\0\0\0H\276\0\340\377\377\376\177\0\0\270\v\0\0\0\17\0051\377H\2155"..., iov_len=57}], 3) = 177
openat(AT_FDCWD, "/proc/self/fd/3", O_RDONLY|O_CLOEXEC) = 4
close(3)                                = 0
pipe([3, 5])                            = 0
dup2(5, 0)                              = 0
clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLDstrace: Process 10680 attached
, child_tidptr=0x7f48d77b7a10) = 10680
[pid 10680] set_robust_list(0x7f48d77b7a20, 24 <unfinished ...>
[pid 10678] read(3,  <unfinished ...>
[pid 10680] <... set_robust_list resumed>) = 0
[pid 10680] execveat(4, "", NULL, NULL, AT_EMPTY_PATH) = 0
[pid 10680] munmap(0x100001000, 140733193379840) = 0
[pid 10680] write(0, "\272", 1)         = 1
[pid 10678] <... read resumed>"\272", 1) = 1
[pid 10680] pause( <unfinished ...>
[pid 10678] newfstatat(4, "", {st_mode=S_IFREG|0700, st_size=177, ...}, AT_EMPTY_PATH) = 0
[pid 10678] openat(AT_FDCWD, "/proc/10680/maps", O_RDONLY) = 6
[pid 10678] read(6, "100000000-100001000 r-xp 0000000"..., 256) = 175
[pid 10678] getrandom("\x39\xfb\x5d\x5b\x64\xbf\x58\x89", 8, GRND_NONBLOCK) = 8
[pid 10678] brk(NULL)                   = 0x55cafcf35000
[pid 10678] brk(0x55cafcf56000)         = 0x55cafcf56000
[pid 10678] write(2, "proc-pid-vm: proc-pid-vm.c:389: "..., 68proc-pid-vm: proc-pid-vm.c:389: main: Assertion `rv == len' failed.
) = 68
[pid 10678] mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f48d79c2000
[pid 10678] rt_sigprocmask(SIG_UNBLOCK, [ABRT], NULL, 8) = 0
[pid 10678] gettid()                    = 10678
[pid 10678] getpid()                    = 10678
[pid 10678] tgkill(10678, 10678, SIGABRT) = 0
[pid 10678] --- SIGABRT {si_signo=SIGABRT, si_code=SI_TKILL, si_pid=10678, si_uid=0} ---
[pid 10678] +++ killed by SIGABRT +++
<... pause resumed>)                    = ? ERESTARTNOHAND (To be restarted if no handler)
strace: Process 10680 detached