On 7/26/19 6:48 PM, Bart Van Assche wrote: > 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@xxxxxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Hannes Reinecke <hare@xxxxxxxx> > Cc: Johannes Thumshirn <jthumshirn@xxxxxxx> > Cc: Ming Lei <ming.lei@xxxxxxxxxx> > Cc: Jan Palus <jpalus@xxxxxxxxxxxx> > Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> > --- > 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 39b8cc4574b4..c6ed0b12e807 100644 > --- a/drivers/scsi/scsi_logging.c > +++ b/drivers/scsi/scsi_logging.c > @@ -15,57 +15,15 @@ > #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 e03bd9d41fa8..7b196d234626 100644 > --- a/include/scsi/scsi_dbg.h > +++ b/include/scsi/scsi_dbg.h > @@ -6,8 +6,6 @@ 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); > Nope. You've just disabled the prime reason why I did implement SCSI logging; namely to provide per-cpu buffers where messages can be printed into. We can move to kmalloc (or even kvmalloc), but the per-cpu pointer need to be kept. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 21284 (AG Nürnberg)
