Re: [PATCH v3 2/2] serial: 8250: Add proper clock handling for OxSemi PCIe devices

[Maciej W. Rozycki]

On Thu, 17 Feb 2022, Dan Carpenter wrote:

> url:    https://github.com/0day-ci/linux/commits/Maciej-W-Rozycki/serial-8250-Fixes-for-Oxford-Semiconductor-950-UARTs/20220212-164255
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
> config: x86_64-randconfig-m001 (https://download.01.org/0day-ci/archive/20220213/202202130027.ZKBCgtm5-lkp@xxxxxxxxx/config)
> compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> 
> New smatch warnings:
> drivers/tty/serial/8250/8250_pci.c:1171 pci_oxsemi_tornado_get_divisor() error: uninitialized symbol 'tcr'.
> drivers/tty/serial/8250/8250_pci.c:1172 pci_oxsemi_tornado_get_divisor() error: uninitialized symbol 'quot'.
> drivers/tty/serial/8250/8250_pci.c:1180 pci_oxsemi_tornado_get_divisor() error: uninitialized symbol 'cpr'.

 These variables do get assigned to in the first iteration of the loop, 
because the deviation calculated (`srem') is normalised to the range of 
[0,spre/2] and that divided by the original divisor (`spre') always works 
out at within [0,0.5], so `squot' will be within [0,32768].  I guess the 
static analyser is too dumb to figure it out, so I'll see how to paper it 
over unless someone has a better proposal.

 Greg: shall I send an update patch or a replacement v4 of the series?

  Maciej