On Thu, 21 Jan 2021, Jiri Kosina wrote: > I am currently waiting for confirmation by the original reporter that the > patch below fixes the issue. ... a now a patch that actually compiles :) (made a mistake when forward-porting from the older kernel on which this has been reported). From: Jiri Kosina <jkosina@xxxxxxx> Subject: [PATCH v2] floppy: reintroduce O_NDELAY fix Originally fixed in 09954bad4 ("floppy: refactor open() flags handling") then reverted for unknown reason in f2791e7eadf437 instead of taking the open(O_ACCMODE) for ioctl-only open fix, which had the changelog below ==== Commit 09954bad4 ("floppy: refactor open() flags handling"), as a side-effect, causes open(/dev/fdX, O_ACCMODE) to fail. It turns out that this is being used setfdprm userspace for ioctl-only open(). Reintroduce back the original behavior wrt !(FMODE_READ|FMODE_WRITE) modes, while still keeping the original O_NDELAY bug fixed. Cc: stable@xxxxxxxxxxxxxxx # v4.5+ Reported-by: Wim Osterholt <wim@xxxxxxxxxxxxxx> Tested-by: Wim Osterholt <wim@xxxxxxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> ===== Fixes: 09954bad4 ("floppy: refactor open() flags handling") Fixes: f2791e7ead ("Revert "floppy: refactor open() flags handling"") Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> --- v1 -> v2: fix build issue due to bad forward-port drivers/block/floppy.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index dfe1dfc901cc..f9e839c8c5aa 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -4121,23 +4121,23 @@ static int floppy_open(struct block_device *bdev, fmode_t mode) if (fdc_state[FDC(drive)].rawcmd == 1) fdc_state[FDC(drive)].rawcmd = 2; - if (!(mode & FMODE_NDELAY)) { - if (mode & (FMODE_READ|FMODE_WRITE)) { - drive_state[drive].last_checked = 0; - clear_bit(FD_OPEN_SHOULD_FAIL_BIT, - &drive_state[drive].flags); - if (bdev_check_media_change(bdev)) - floppy_revalidate(bdev->bd_disk); - if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags)) - goto out; - if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags)) - goto out; - } - res = -EROFS; - if ((mode & FMODE_WRITE) && - !test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags)) + if (mode & (FMODE_READ|FMODE_WRITE)) { + UDRS->last_checked = 0; + clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags); + if (bdev_check_media_change(bdev)) + floppy_revalidate(bdev->bd_disk); + if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags)) + goto out; + if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags)) goto out; } + + res = -EROFS; + + if ((mode & FMODE_WRITE) && + !test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags)) + goto out; + mutex_unlock(&open_lock); mutex_unlock(&floppy_mutex); return 0; -- Jiri Kosina SUSE Labs