[PATCH] mm: fix missed initialization for folio_batch::percpu_pvec_drained
From: Changbin Du
Date: Sun Jan 16 2022 - 02:03:09 EST
The folio_batch_init() forgets to initinize folio_batch::percpu_pvec_drained.
This can be detected by UBSAN tool.
[ 6.990914][ T1] ========================================================================
[ 6.991968][ T1] UBSAN: invalid-load in mm/swap.c:996:11
[ 6.993429][ T1] load of value 124 is not a valid value for type '_Bool'
[ 6.994774][ T1] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.16.0-09673-ga33f5c380c4b #27
[ 6.995909][ T1] Hardware name: riscv-virtio,qemu (DT)
[ 6.996898][ T1] Call Trace:
[ 6.997608][ T1] [<ffffffff80005ee6>] dump_backtrace+0x30/0x38
[ 6.998307][ T1] [<ffffffff80912a9a>] dump_stack_lvl+0x58/0x7a
[ 6.998822][ T1] [<ffffffff80912ad4>] dump_stack+0x18/0x20
[ 6.999334][ T1] [<ffffffff8091276e>] ubsan_epilogue+0x10/0x58
[ 6.999938][ T1] [<ffffffff8052f84a>] __ubsan_handle_load_invalid_value+0x84/0x86
[ 7.000626][ T1] [<ffffffff801927ea>] __pagevec_release+0x6c/0x72
[ 7.001212][ T1] [<ffffffff80193776>] truncate_inode_pages_range+0x152/0x4a6
[ 7.001839][ T1] [<ffffffff80193aec>] truncate_inode_pages+0x22/0x2a
[ 7.002397][ T1] [<ffffffff8045fb60>] blkdev_flush_mapping+0x78/0x13e
[ 7.002960][ T1] [<ffffffff80460046>] blkdev_put+0x1a6/0x1f8
[ 7.003482][ T1] [<ffffffff804811c2>] disk_scan_partitions+0x5c/0x78
[ 7.004069][ T1] [<ffffffff8048147e>] device_add_disk+0x2a0/0x2c0
[ 7.004627][ T1] [<ffffffff8060f2a6>] virtblk_probe+0x68c/0xb20
[ 7.005176][ T1] [<ffffffff805989dc>] virtio_dev_probe+0x12e/0x210
[ 7.005718][ T1] [<ffffffff805eba02>] really_probe.part.0+0x6c/0x24e
[ 7.006266][ T1] [<ffffffff805ebcc0>] __driver_probe_device+0xdc/0x13e
[ 7.006847][ T1] [<ffffffff805ebd62>] driver_probe_device+0x40/0x10c
[ 7.007451][ T1] [<ffffffff805ec5a2>] __driver_attach+0x8c/0x172
[ 7.008036][ T1] [<ffffffff805e946a>] bus_for_each_dev+0x6a/0xa8
[ 7.008617][ T1] [<ffffffff805eb140>] driver_attach+0x2e/0x36
[ 7.009159][ T1] [<ffffffff805eab80>] bus_add_driver+0x170/0x1ee
[ 7.009717][ T1] [<ffffffff805ece74>] driver_register+0x66/0xfe
[ 7.010295][ T1] [<ffffffff805987fa>] register_virtio_driver+0x30/0x4e
[ 7.010899][ T1] [<ffffffff80a2a116>] init+0x78/0xac
[ 7.011381][ T1] [<ffffffff800025e8>] do_one_initcall+0x7e/0x262
[ 7.011955][ T1] [<ffffffff80a0197e>] kernel_init_freeable+0x30e/0x372
[ 7.012559][ T1] [<ffffffff8091846a>] kernel_init+0x32/0x178
[ 7.013105][ T1] [<ffffffff80003cda>] ret_from_exception+0x0/0x14
[ 7.015034][ T1] ========================================================================
Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>
---
include/linux/pagevec.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/linux/pagevec.h b/include/linux/pagevec.h
index dda8d5868c81..67b1246f136b 100644
--- a/include/linux/pagevec.h
+++ b/include/linux/pagevec.h
@@ -111,6 +111,7 @@ static_assert(offsetof(struct pagevec, pages) ==
static inline void folio_batch_init(struct folio_batch *fbatch)
{
fbatch->nr = 0;
+ fbatch->percpu_pvec_drained = false;
}
static inline unsigned int folio_batch_count(struct folio_batch *fbatch)
--
2.32.0