From: Bart Van Assche bvanassche@acm.org
[ Upstream commit dccc96abfb21dc19d69e707c38c8ba439bba7160 ]
The data structure used for log messages is so large that it can cause a boot failure. Since allocations from that data structure can fail anyway, use kmalloc() / kfree() instead of that data structure.
See also https://bugzilla.kernel.org/show_bug.cgi?id=204119. See also commit ded85c193a39 ("scsi: Implement per-cpu logging buffer") # v4.0.
Reported-by: Jan Palus jpalus@fastmail.com Cc: Christoph Hellwig hch@lst.de Cc: Hannes Reinecke hare@suse.com Cc: Johannes Thumshirn jthumshirn@suse.de Cc: Ming Lei ming.lei@redhat.com Cc: Jan Palus jpalus@fastmail.com Signed-off-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/scsi_logging.c | 48 +++---------------------------------- include/scsi/scsi_dbg.h | 2 -- 2 files changed, 3 insertions(+), 47 deletions(-)
diff --git a/drivers/scsi/scsi_logging.c b/drivers/scsi/scsi_logging.c index bd70339c1242e..03d9855a6afd7 100644 --- a/drivers/scsi/scsi_logging.c +++ b/drivers/scsi/scsi_logging.c @@ -16,57 +16,15 @@ #include <scsi/scsi_eh.h> #include <scsi/scsi_dbg.h>
-#define SCSI_LOG_SPOOLSIZE 4096 - -#if (SCSI_LOG_SPOOLSIZE / SCSI_LOG_BUFSIZE) > BITS_PER_LONG -#warning SCSI logging bitmask too large -#endif - -struct scsi_log_buf { - char buffer[SCSI_LOG_SPOOLSIZE]; - unsigned long map; -}; - -static DEFINE_PER_CPU(struct scsi_log_buf, scsi_format_log); - static char *scsi_log_reserve_buffer(size_t *len) { - struct scsi_log_buf *buf; - unsigned long map_bits = sizeof(buf->buffer) / SCSI_LOG_BUFSIZE; - unsigned long idx = 0; - - preempt_disable(); - buf = this_cpu_ptr(&scsi_format_log); - idx = find_first_zero_bit(&buf->map, map_bits); - if (likely(idx < map_bits)) { - while (test_and_set_bit(idx, &buf->map)) { - idx = find_next_zero_bit(&buf->map, map_bits, idx); - if (idx >= map_bits) - break; - } - } - if (WARN_ON(idx >= map_bits)) { - preempt_enable(); - return NULL; - } - *len = SCSI_LOG_BUFSIZE; - return buf->buffer + idx * SCSI_LOG_BUFSIZE; + *len = 128; + return kmalloc(*len, GFP_ATOMIC); }
static void scsi_log_release_buffer(char *bufptr) { - struct scsi_log_buf *buf; - unsigned long idx; - int ret; - - buf = this_cpu_ptr(&scsi_format_log); - if (bufptr >= buf->buffer && - bufptr < buf->buffer + SCSI_LOG_SPOOLSIZE) { - idx = (bufptr - buf->buffer) / SCSI_LOG_BUFSIZE; - ret = test_and_clear_bit(idx, &buf->map); - WARN_ON(!ret); - } - preempt_enable(); + kfree(bufptr); }
static inline const char *scmd_name(const struct scsi_cmnd *scmd) diff --git a/include/scsi/scsi_dbg.h b/include/scsi/scsi_dbg.h index f8170e90b49d2..bbe71a6361db9 100644 --- a/include/scsi/scsi_dbg.h +++ b/include/scsi/scsi_dbg.h @@ -5,8 +5,6 @@ struct scsi_cmnd; struct scsi_device; struct scsi_sense_hdr;
-#define SCSI_LOG_BUFSIZE 128 - extern void scsi_print_command(struct scsi_cmnd *); extern size_t __scsi_format_command(char *, size_t, const unsigned char *, size_t);