KAMEZAWA Hiroyuki wrote:
> This is reproducer of panic. "quick fix" is attached.
> But I think putback_lru_page() should be re-designed.
>
> ==
> #include <stdio.h>
> #include <sys/types.h>
> #include <sys/stat.h>
> #include <fcntl.h>
> #include <sys/mman.h>
> #include <unistd.h>
> #include <errno.h>
>
> int main(int argc, char *argv[])
> {
> int fd;
> char *filename = argv[1];
> char buffer[4096];
> char *addr;
> int len;
>
> fd = open(filename, O_CREAT | O_EXCL | O_RDWR, S_IRWXU);
>
> if (fd < 0) {
> perror("open");
> exit(1);
> }
> len = write(fd, buffer, sizeof(buffer));
>
> if (len < 0) {
> perror("write");
> exit(1);
> }
>
> addr = mmap(NULL, 4096, PROT_WRITE, MAP_SHARED|MAP_LOCKED, fd, 0);
> if (addr == MAP_FAILED) {
> perror("mmap");
> exit(1);
> }
> munmap(addr, 4096);
> close(fd);
>
> unlink(filename);
> }
> ==
> you'll see panic.
>
> Fix is here
> ==
Hi Kame,
Thanks, The patch fixes the kernel panic.
Tested-by: Kamalesh Babulal <kamalesh@xxxxxxxxxxxxxxxxxx>
>
> quick fix for double unlock_page();
>
> Signed-off-by: KAMEZAWA Hiroyuki <kamewzawa.hiroyu@xxxxxxxxxxxxxx>
> Index: linux-2.6.26-rc5-mm3/mm/truncate.c
> ===================================================================
> --- linux-2.6.26-rc5-mm3.orig/mm/truncate.c
> +++ linux-2.6.26-rc5-mm3/mm/truncate.c
> @@ -104,8 +104,8 @@ truncate_complete_page(struct address_sp
>
> cancel_dirty_page(page, PAGE_CACHE_SIZE);
>
> - remove_from_page_cache(page);
> clear_page_mlock(page);
> + remove_from_page_cache(page);
> ClearPageUptodate(page);
> ClearPageMappedToDisk(page);
> page_cache_release(page); /* pagecache ref */
>
--
Thanks & Regards,
Kamalesh Babulal,
Linux Technology Center,
IBM, ISTL.
--
To unsubscribe from this list: send the line "unsubscribe kernel-testers" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
