On Thu, Dec 12, 2019 at 6:15 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote: > > This patchset extends kcov to allow collecting coverage from interrupts > and then uses the new functionality to collect coverage from usbhid code. > > What I'm not sure yet about this change is if we actually want to > selectively annotate some parts of the USB stack that are executed in > interrupt context, or maybe we can do this with some common approach. > > For example patch #2 in this patchset annotates all functions that are > passed as completion callbacks to usb_fill_*() in drivers/hid/usbhid. > Maybe instead we could redefine usb_fill_*() in a way that would handle > all such cases without manual annotations. Although looking at this again today, it seems much more logical to add kcov annotations around the complete() callback in __usb_hcd_giveback_urb(). Don't know why I didn't think of that. Will do in the next version. > > Any suggestions are welcome. > > This has allowed to find at least one new HID bug [1], which was recently > fixed by Alan [2]. > > [1] https://syzkaller.appspot.com/bug?extid=09ef48aa58261464b621 > [2] https://patchwork.kernel.org/patch/11283319/ > > This patchset has been pushed to the public Linux kernel Gerrit instance: > > https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/2225 > > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > > Andrey Konovalov (2): > kcov: collect coverage from interrupts > HID: usbhid: kcov: add annotations for coverage collection > > Documentation/dev-tools/kcov.rst | 16 +-- > drivers/hid/usbhid/hid-core.c | 25 +++- > drivers/hid/usbhid/usbkbd.c | 15 ++- > drivers/hid/usbhid/usbmouse.c | 7 +- > drivers/usb/gadget/udc/dummy_hcd.c | 1 + > include/linux/sched.h | 3 + > kernel/kcov.c | 196 +++++++++++++++++++---------- > lib/Kconfig.debug | 9 ++ > 8 files changed, 192 insertions(+), 80 deletions(-) > > -- > 2.24.1.735.g03f4e72817-goog >
