4.16-stable review patch. If anyone has any objections, please let me know.
------------------ From: Alexey Dobriyan <[email protected]> [ Upstream commit 9a1015b32faa7cebfe19663c886b0cfe90be1d49 ] Commit 95846ecf9dac ("pid: replace pid bitmap implementation with IDR API") changed last field of /proc/loadavg (last pid allocated) to be off by one: # unshare -p -f --mount-proc cat /proc/loadavg 0.00 0.00 0.00 1/60 2 <=== It should be 1 after first fork into pid namespace. This is formally a regression but given how useless this field is I don't think anyone is affected. Bug was found by /proc testsuite! Link: http://lkml.kernel.org/r/20180413175408.GA27246@avx2 Fixes: 95846ecf9dac508 ("pid: replace pid bitmap implementation with IDR API") Signed-off-by: Alexey Dobriyan <[email protected]> Cc: "Eric W. Biederman" <[email protected]> Cc: Gargi Sharma <[email protected]> Cc: Oleg Nesterov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/powerpc/platforms/cell/spufs/sched.c | 2 +- fs/proc/loadavg.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -1093,7 +1093,7 @@ static int show_spu_loadavg(struct seq_f LOAD_INT(c), LOAD_FRAC(c), count_active_contexts(), atomic_read(&nr_spu_contexts), - idr_get_cursor(&task_active_pid_ns(current)->idr)); + idr_get_cursor(&task_active_pid_ns(current)->idr) - 1); return 0; } --- a/fs/proc/loadavg.c +++ b/fs/proc/loadavg.c @@ -24,7 +24,7 @@ static int loadavg_proc_show(struct seq_ LOAD_INT(avnrun[1]), LOAD_FRAC(avnrun[1]), LOAD_INT(avnrun[2]), LOAD_FRAC(avnrun[2]), nr_running(), nr_threads, - idr_get_cursor(&task_active_pid_ns(current)->idr)); + idr_get_cursor(&task_active_pid_ns(current)->idr) - 1); return 0; }
