Add informational messages during blktrace setup when version 1 tools are used on kernels with CONFIG_BLK_DEV_ZONED enabled. This alerts users that REQ_OP_ZONE_* events will be dropped and suggests upgrading to blktrace tools version 2 or later. The warning is printed once during trace setup to inform users about the limitation without spamming the logs during tracing operations. Version 2 blktrace tools properly handle zone management operations (zone reset, zone open, zone close, zone finish, zone append) that were added for zoned block devices. * With old blktrace tool and this patch :- blktests (master) # ./check blktrace/ blktrace/001 (blktrace zone management command tracing) [passed] runtime 3.706s ... 3.735s blktrace/002 (blktrace ftrace corruption with sysfs trace) [passed] runtime 0.479s ... 0.456s blktests (master) # dmesg -c [ 9455.610899] null_blk: disk nullb0 created [ 9455.610916] null_blk: module loaded [ 9455.634103] run blktests blktrace/001 at 2026-02-02 15:02:23 [ 9455.651710] null_blk: nullb1: using native zone append [ 9455.662852] null_blk: disk nullb1 created *[ 9455.714998] blktrace: nullb1: blktrace events for zone operations will be dropped* *[ 9455.715065] blktrace: use blktrace tools version >= 2 to track zone operations* [ 9459.480181] null_blk: disk nullb0 created [ 9459.480199] null_blk: module loaded [ 9459.514464] run blktests blktrace/002 at 2026-02-02 15:02:27 [ 9459.541772] null_blk: disk nullb1 created blktests (master) # * With new blktrace tools and this patch :- blktests (master) # ./check blktrace/ blktrace/001 (blktrace zone management command tracing) [passed] runtime 3.735s ... 3.734s blktrace/002 (blktrace ftrace corruption with sysfs trace) [passed] runtime 0.456s ... 0.496s blktests (master) # dmesg -c [ 9490.395572] null_blk: disk nullb0 created [ 9490.395591] null_blk: module loaded [ 9490.419467] run blktests blktrace/001 at 2026-02-02 15:02:58 [ 9490.436416] null_blk: nullb1: using native zone append [ 9490.447806] null_blk: disk nullb1 created [ 9494.262176] null_blk: disk nullb0 created [ 9494.262195] null_blk: module loaded [ 9494.296653] run blktests blktrace/002 at 2026-02-02 15:03:02 [ 9494.322261] null_blk: disk nullb1 created blktests (master) # This helps users understand why zone operation traces may be missing when using older blktrace tool versions with modern kernels that support REQ_OP_ZONE_XXX in blktrace. Reviewed-by: Damien Le Moal Signed-off-by: Chaitanya Kulkarni --- V3->V4:- Replace REQ_OP_ZONE_XXX with "zone operations". (Damien, Jens) --- kernel/trace/blktrace.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index d031c8d80be4..04b41c698127 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -741,6 +741,12 @@ static void blk_trace_setup_finalize(struct request_queue *q, * to underscores for this to work as expected */ strreplace(buts->name, '/', '_'); + if (version == 1 && IS_ENABLED(CONFIG_BLK_DEV_ZONED)) { + pr_info("%s: blktrace events for zone operations will be dropped\n", + name); + pr_info("use blktrace tools version >= 2 to track zone operations\n"); + + } bt->version = version; bt->act_mask = buts->act_mask; -- 2.39.5