Re: nfs: lock stuck after interrupt

From: Miklos Szeredi
Date: Fri Apr 18 2008 - 07:08:26 EST


> We brought up this specific issue a few weeks ago in this thread:
>
> http://marc.info/?l=linux-nfs&m=120663578712912&w=2
>
> While we had a fix that tested out properly (third reply in the
> thread), I believe Trond fixed this recently in a more "correct"
> method with this patch (and series):
>
> http://marc.info/?l=linux-nfs&m=120726349027607&w=2
>
> We haven't had the opportunity to check Tronds' patch yet though.

Thanks for the info.

1) I pulled the devel branch of nfs-2.6.git and tested the same setup,
with exactly the same result as previously.

2) then I added your patch on top of that, which did change something
but not really for the better: now even the restarted lock request
doesn't succeed after the interrupt.

According to my suspicion, this is an issue in the server, while both
referenced patches touch only the client.

Appended little test program which I'm trying out locking with.

Miklos
---

#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <signal.h>

static void int_handler(int s)
{
(void) s;
fprintf(stderr, "signal caught\n");
}

int main(int argc, char *argv[])
{
char *filename = argv[1];
int res;
int fd;

if (argc != 2) {
fprintf(stderr, "usage: %s filename\n", argv[0]);
return 1;
}

signal(SIGINT, int_handler);

fd = open(filename, O_RDWR | O_CREAT, 0666);
if (fd == -1) {
perror("open");
return 1;
}

res = lockf(fd, F_LOCK, 100);
if (res == -1) {
perror("lockf");
return 1;
}
printf("locked\n");
pause();
return 0;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/