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| author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2018-10-09 14:12:00 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-10-09 17:25:07 +0300 |
| commit | 7325b4bbe5952e3e939f15de812f2ee0c0d33ca9 (patch) | |
| tree | 560d344890b628460494963269b45e917187113f /drivers/lightnvm | |
| parent | bf82fa2f584f1c6e12df8c04fca715d53e7f32d5 (diff) | |
| download | linux-7325b4bbe5952e3e939f15de812f2ee0c0d33ca9.tar.xz | |
lightnvm: pblk: fix two sleep-in-atomic-context bugs
The driver may sleep with holding a spinlock.
The function call paths (from bottom to top) in Linux-4.16 are:
[FUNC] nvm_dev_dma_alloc(GFP_KERNEL)
drivers/lightnvm/pblk-core.c, 754:
nvm_dev_dma_alloc in pblk_line_submit_smeta_io
drivers/lightnvm/pblk-core.c, 1048:
pblk_line_submit_smeta_io in pblk_line_init_bb
drivers/lightnvm/pblk-core.c, 1434:
pblk_line_init_bb in pblk_line_replace_data
drivers/lightnvm/pblk-recovery.c, 980:
pblk_line_replace_data in pblk_recov_l2p
drivers/lightnvm/pblk-recovery.c, 976:
spin_lock in pblk_recov_l2p
[FUNC] bio_map_kern(GFP_KERNEL)
drivers/lightnvm/pblk-core.c, 762:
bio_map_kern in pblk_line_submit_smeta_io
drivers/lightnvm/pblk-core.c, 1048:
pblk_line_submit_smeta_io in pblk_line_init_bb
drivers/lightnvm/pblk-core.c, 1434:
pblk_line_init_bb in pblk_line_replace_data
drivers/lightnvm/pblk-recovery.c, 980:
pblk_line_replace_data in pblk_recov_l2p
drivers/lightnvm/pblk-recovery.c, 976:
spin_lock in pblk_recov_l2p
To fix these bugs, the call to pblk_line_replace_data()
is moved out of the spinlock protection.
These bugs are found by my static analysis tool DSAC.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/lightnvm')
| -rw-r--r-- | drivers/lightnvm/pblk-recovery.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c index 8036c3eb6372..2526722304bb 100644 --- a/drivers/lightnvm/pblk-recovery.c +++ b/drivers/lightnvm/pblk-recovery.c @@ -966,12 +966,14 @@ next: } } - spin_lock(&l_mg->free_lock); if (!open_lines) { + spin_lock(&l_mg->free_lock); WARN_ON_ONCE(!test_and_clear_bit(meta_line, &l_mg->meta_bitmap)); + spin_unlock(&l_mg->free_lock); pblk_line_replace_data(pblk); } else { + spin_lock(&l_mg->free_lock); /* Allocate next line for preparation */ l_mg->data_next = pblk_line_get(pblk); if (l_mg->data_next) { @@ -979,8 +981,8 @@ next: l_mg->data_next->type = PBLK_LINETYPE_DATA; is_next = 1; } + spin_unlock(&l_mg->free_lock); } - spin_unlock(&l_mg->free_lock); if (is_next) pblk_line_erase(pblk, l_mg->data_next); |