diff options
| author | Kees Cook <keescook@chromium.org> | 2018-11-30 14:36:58 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-11 12:21:48 +0200 |
| commit | f72ecfe93a80a1e83bc9b13f2c66c8af3fb456d8 (patch) | |
| tree | cd5aebaade00aee5c6463eb2f3ef4f16ba4b42ef /drivers/firmware | |
| parent | d80d6f65fb9aece7a624baae5dc9a968d97d0953 (diff) | |
pstore: Convert buf_lock to semaphore
commit ea84b580b95521644429cc6748b6c2bf27c8b0f3 upstream.
Instead of running with interrupts disabled, use a semaphore. This should
make it easier for backends that may need to sleep (e.g. EFI) when
performing a write:
|BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
|in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum
|Preemption disabled at:
|[<ffffffff99d60512>] pstore_dump+0x72/0x330
|CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45
|Call Trace:
| dump_stack+0x4f/0x6a
| ___might_sleep.cold.91+0xd3/0xe4
| __might_sleep+0x50/0x90
| wait_for_completion+0x32/0x130
| virt_efi_query_variable_info+0x14e/0x160
| efi_query_variable_store+0x51/0x1a0
| efivar_entry_set_safe+0xa3/0x1b0
| efi_pstore_write+0x109/0x140
| pstore_dump+0x11c/0x330
| kmsg_dump+0xa4/0xd0
| oops_exit+0x22/0x30
...
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Fixes: 21b3ddd39fee ("efi: Don't use spinlocks for efi vars")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efi/efi-pstore.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c index 5a0fa939d70f..4277147f7140 100644 --- a/drivers/firmware/efi/efi-pstore.c +++ b/drivers/firmware/efi/efi-pstore.c @@ -258,8 +258,7 @@ static int efi_pstore_write(struct pstore_record *record) efi_name[i] = name[i]; ret = efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES, - !pstore_cannot_block_path(record->reason), - record->size, record->psi->buf); + preemptible(), record->size, record->psi->buf); if (record->reason == KMSG_DUMP_OOPS) efivar_run_worker(); @@ -368,7 +367,6 @@ static __init int efivars_pstore_init(void) return -ENOMEM; efi_pstore_info.bufsize = 1024; - spin_lock_init(&efi_pstore_info.buf_lock); if (pstore_register(&efi_pstore_info)) { kfree(efi_pstore_info.buf); |