| Message ID | 20200610134919.73688-1-yuehaibing@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ext4: mballoc: Disable preemption before getting per-CPU pointer | expand |
Hello, Fix for this is already submitted @ https://patchwork.ozlabs.org/project/linux-ext4/patch/534f275016296996f54ecf65168bb3392b6f653d.1591699601.git.riteshh@linux.ibm.com/ -ritesh On 6/10/20 7:19 PM, YueHaibing wrote: > BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u16:3/2181 > caller is ext4_mb_new_blocks+0x388/0xed0 > CPU: 2 PID: 2181 Comm: kworker/u16:3 Not tainted 5.7.0+ #182 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > Workqueue: writeback wb_workfn (flush-8:0) > Call Trace: > dump_stack+0xb9/0xfc > debug_smp_processor_id+0xc8/0xd0 > ext4_mb_new_blocks+0x388/0xed0 > ext4_ext_map_blocks+0xa92/0xff0 > ext4_map_blocks+0x34e/0x580 > ext4_writepages+0xa28/0x11b0 > do_writepages+0x46/0xe0 > __writeback_single_inode+0x5f/0x6b0 > writeback_sb_inodes+0x290/0x620 > __writeback_inodes_wb+0x62/0xb0 > wb_writeback+0x36c/0x520 > wb_workfn+0x319/0x680 > process_one_work+0x271/0x640 > worker_thread+0x3a/0x3a0 > kthread+0x14e/0x170 > ret_from_fork+0x27/0x40 > > Disable preemption before accessing discard_pa_seq. > > Fixes: 07b5b8e1ac40 ("ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling") > Signed-off-by: YueHaibing <yuehaibing@huawei.com> > --- > fs/ext4/mballoc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index a9083113a8c0..30b3bfb1e06a 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -4708,7 +4708,8 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle, > } > > ac->ac_op = EXT4_MB_HISTORY_PREALLOC; > - seq = *this_cpu_ptr(&discard_pa_seq); > + seq = *get_cpu_ptr(&discard_pa_seq); > + put_cpu_ptr(&discard_pa_seq); > if (!ext4_mb_use_preallocated(ac)) { > ac->ac_op = EXT4_MB_HISTORY_ALLOC; > ext4_mb_normalize_request(ac, ar); >
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index a9083113a8c0..30b3bfb1e06a 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4708,7 +4708,8 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle, } ac->ac_op = EXT4_MB_HISTORY_PREALLOC; - seq = *this_cpu_ptr(&discard_pa_seq); + seq = *get_cpu_ptr(&discard_pa_seq); + put_cpu_ptr(&discard_pa_seq); if (!ext4_mb_use_preallocated(ac)) { ac->ac_op = EXT4_MB_HISTORY_ALLOC; ext4_mb_normalize_request(ac, ar);
BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u16:3/2181 caller is ext4_mb_new_blocks+0x388/0xed0 CPU: 2 PID: 2181 Comm: kworker/u16:3 Not tainted 5.7.0+ #182 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Workqueue: writeback wb_workfn (flush-8:0) Call Trace: dump_stack+0xb9/0xfc debug_smp_processor_id+0xc8/0xd0 ext4_mb_new_blocks+0x388/0xed0 ext4_ext_map_blocks+0xa92/0xff0 ext4_map_blocks+0x34e/0x580 ext4_writepages+0xa28/0x11b0 do_writepages+0x46/0xe0 __writeback_single_inode+0x5f/0x6b0 writeback_sb_inodes+0x290/0x620 __writeback_inodes_wb+0x62/0xb0 wb_writeback+0x36c/0x520 wb_workfn+0x319/0x680 process_one_work+0x271/0x640 worker_thread+0x3a/0x3a0 kthread+0x14e/0x170 ret_from_fork+0x27/0x40 Disable preemption before accessing discard_pa_seq. Fixes: 07b5b8e1ac40 ("ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling") Signed-off-by: YueHaibing <yuehaibing@huawei.com> --- fs/ext4/mballoc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)