Messages in this thread | | | Date | Mon, 24 Apr 2023 08:34:00 +0200 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH 5.4 v4 3/5] counter: 104-quad-8: Fix race condition between FLAG and CNTR reads |
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On Sun, Apr 23, 2023 at 07:20:45PM -0400, William Breathitt Gray wrote: > commit 4aa3b75c74603c3374877d5fd18ad9cc3a9a62ed upstream. > > The Counter (CNTR) register is 24 bits wide, but we can have an > effective 25-bit count value by setting bit 24 to the XOR of the Borrow > flag and Carry flag. The flags can be read from the FLAG register, but a > race condition exists: the Borrow flag and Carry flag are instantaneous > and could change by the time the count value is read from the CNTR > register. > > Since the race condition could result in an incorrect 25-bit count > value, remove support for 25-bit count values from this driver. > > Fixes: 28e5d3bb0325 ("iio: 104-quad-8: Add IIO support for the ACCES 104-QUAD-8") > Cc: <stable@vger.kernel.org> # 5.4.x > Signed-off-by: William Breathitt Gray <william.gray@linaro.org> > --- > drivers/counter/104-quad-8.c | 20 +++----------------- > 1 file changed, 3 insertions(+), 17 deletions(-) >
This patch also breaks the build, same error as on 5.10.y.
Can you send new 5.4.y and 5.10.y versions? All the other ones were fine.
thanks,
greg k-h
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