The patch titled drivers/usb/misc: Use an IS_ERR test rather than a NULL test has been added to the -mm tree. Its filename is drivers-usb-misc-use-an-is_err-test-rather-than-a-null-test.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: drivers/usb/misc: Use an IS_ERR test rather than a NULL test From: Julien Brunel <brunel@xxxxxxx> In case of error, the function backlight_device_register returns an ERR pointer, but never returns a NULL pointer. So a NULL test that may come after a call to this function should be strengthened by an IS_ERR test. The semantic match that finds this problem is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @match_bad_null_test@ expression x, E; statement S1,S2; @@ x = backlight_device_register(...) ... when != x = E * if (x != NULL) S1 else S2 // </smpl> Signed-off-by: Julien Brunel <brunel@xxxxxxx> Signed-off-by: Julia Lawall <julia@xxxxxxx> Cc: Greg KH <greg@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/usb/misc/appledisplay.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN drivers/usb/misc/appledisplay.c~drivers-usb-misc-use-an-is_err-test-rather-than-a-null-test drivers/usb/misc/appledisplay.c --- a/drivers/usb/misc/appledisplay.c~drivers-usb-misc-use-an-is_err-test-rather-than-a-null-test +++ a/drivers/usb/misc/appledisplay.c @@ -314,7 +314,7 @@ error: pdata->urbdata, pdata->urb->transfer_dma); usb_free_urb(pdata->urb); } - if (pdata->bd) + if (pdata->bd && !IS_ERR(pdata->bd)) backlight_device_unregister(pdata->bd); kfree(pdata->msgdata); } _ Patches currently in -mm which might be from brunel@xxxxxxx are origin.patch linux-next.patch fs-gfs2-use-an-is_err-test-rather-than-a-null-test.patch checkpatch-suppress-errors-triggered-by-short-patch.patch fs-reiserfs-use-an-is_err-test-rather-than-a-null-test.patch drivers-usb-misc-use-an-is_err-test-rather-than-a-null-test.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html