lkml.org 
[lkml]   [2020]   [Jun]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] sched/deadline: Initialize dl_boosted
Date
syzbot reported the following warning:

WARNING: CPU: 0 PID: 6973 at kernel/sched/deadline.c:593 setup_new_dl_entity /kernel/sched/deadline.c:594 [inline]
WARNING: CPU: 0 PID: 6973 at kernel/sched/deadline.c:593 enqueue_dl_entity /kernel/sched/deadline.c:1370 [inline]
WARNING: CPU: 0 PID: 6973 at kernel/sched/deadline.c:593 enqueue_task_dl+0x1c17/0x2ba0 /kernel/sched/deadline.c:1441
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 6973 Comm: syz-executor366 Not tainted 4.14.133 #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack /lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x19c /lib/dump_stack.c:53
panic+0x1f2/0x426 /kernel/panic.c:182
__warn.cold+0x2f/0x36 /kernel/panic.c:546
report_bug+0x216/0x254 /lib/bug.c:186
fixup_bug /arch/x86/kernel/traps.c:177 [inline]
fixup_bug /arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 /arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 /arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 /arch/x86/entry/entry_64.S:960
RIP: 0010:setup_new_dl_entity /kernel/sched/deadline.c:593 [inline]
RIP: 0010:enqueue_dl_entity /kernel/sched/deadline.c:1370 [inline]
RIP: 0010:enqueue_task_dl+0x1c17/0x2ba0 /kernel/sched/deadline.c:1441
RSP: 0018:ffff888098a3fcd8 EFLAGS: 00010002
RAX: 0000000000000000 RBX: ffffffff87ab2780 RCX: 1ffff1101041413a
RDX: 0000000ad48fb497 RSI: ffff8880aee2c518 RDI: ffff8880820a09d0
RBP: ffff888098a3fd48 R08: ffff8880820a09cc R09: ffff8880820a09c0
R10: ffff8880820a073c R11: 0000000000000001 R12: ffff8880820a0700
R13: ffff8880aee2c500 R14: ffff8880820a0978 R15: ffff8880aee2c500
enqueue_task /kernel/sched/core.c:762 [inline]
__sched_setscheduler+0xd17/0x2510 /kernel/sched/core.c:4227
sched_setattr /kernel/sched/core.c:4285 [inline]
SYSC_sched_setattr /kernel/sched/core.c:4456 [inline]
SyS_sched_setattr+0x1f8/0x300 /kernel/sched/core.c:4435
do_syscall_64+0x1e8/0x640 /arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x446749
RSP: 002b:00007ff022092db8 EFLAGS: 00000246 ORIG_RAX: 000000000000013a
RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 0000000000446749
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000
RBP: 00000000006dbc30 R08: 00007ff022093700 R09: 0000000000000000
R10: 00007ff022093700 R11: 0000000000000246 R12: 00000000006dbc3c
R13: 00007ffdbf86bf7f R14: 00007ff0220939c0 R15: 0000000000000000

This happens because dl_boosted flag is currently not initialized by
__dl_clear_params() (unlike the other flags) and setup_new_dl_entity()
finds complains about it.

Initialize dl_boosted to 0.

Reported-by: syzbot+5ac8bac25f95e8b221e7@syzkaller.appspotmail.com
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Daniel Wagner <dwagner@suse.de>
---
kernel/sched/deadline.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 504d2f51b0d6..f63f337c7147 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -2692,6 +2692,7 @@ void __dl_clear_params(struct task_struct *p)
dl_se->dl_bw = 0;
dl_se->dl_density = 0;

+ dl_se->dl_boosted = 0;
dl_se->dl_throttled = 0;
dl_se->dl_yielded = 0;
dl_se->dl_non_contending = 0;
--
2.26.2
\
 
 \ /
  Last update: 2020-06-17 09:30    [W:0.086 / U:0.400 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site