Re: [v6] misc: pci_endpoint_test: Fix overflow of bar_size

[Niklas Cassel <cassel@kernel.org>]

On Thu, Jan 02, 2025 at 08:02:22PM +0800, Hans Zhang wrote:
> With 8GB BAR2, running pcitest -b 2 fails with "TEST FAILED".
>
> The return value of the `pci_resource_len` interface is not an integer.
> Using `pcitest` with an 8GB BAR2, the bar_size of integer type will
> overflow.
> Change the data type of bar_size from integer to resource_size_t, to fix
> the above issue.
>
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202501021000.7Cwcopot-lkp@intel.com/
> Closes: https://lore.kernel.org/oe-kbuild-all/202501011917.ugP1ywJV-lkp@intel.com/

Note that you do not need "Reported-by" and "Closes" tags in this case,
see the earlier text from the kernel test bot:

"""
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202501011917.ugP1ywJV-lkp@intel.com/
"""

In your case, you are fixing it in a new version of the same patch/commit,
so no need to add the tags.


> Signed-off-by: Hans Zhang <18255117159@163.com>
> Reviewed-by: Niklas Cassel <cassel@kernel.org>
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
>

Remove the stray new line above.

> ---
> Changes since v4-v6:
> https://lore.kernel.org/linux-pci/20241231065500.168799-1-18255117159@163.com/
>
> - Fix undefined reference to `__udivmoddi4`
>
> Changes since v3:
> https://lore.kernel.org/linux-pci/20241221141009.27317-1-18255117159@163.com/
>
> - The patch subject were modified.
>
> Changes since v2:
> https://lore.kernel.org/linux-pci/20241220075253.16791-1-18255117159@163.com/
>
> - Fix "changes" part goes below the --- line
> - The patch commit message were modified.
>
> Changes since v1:
> https://lore.kernel.org/linux-pci/20241217121220.19676-1-18255117159@163.com/
>
> - The patch subject and commit message were modified.
> ---
>  drivers/misc/pci_endpoint_test.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
> index 3aaaf47fa4ee..df34b742f2de 100644
> --- a/drivers/misc/pci_endpoint_test.c
> +++ b/drivers/misc/pci_endpoint_test.c
> @@ -280,10 +280,11 @@ static int pci_endpoint_test_bar_memcmp(struct pci_endpoint_test *test,
>  static bool pci_endpoint_test_bar(struct pci_endpoint_test *test,
>				  enum pci_barno barno)
>  {
> -	int j, bar_size, buf_size, iters, remain;
>	void *write_buf __free(kfree) = NULL;
>	void *read_buf __free(kfree) = NULL;
>	struct pci_dev *pdev = test->pdev;
> +	int j, buf_size, iters, remain;
> +	resource_size_t bar_size;
>
>	if (!test->bar[barno])
>		return false;
> @@ -307,13 +308,13 @@ static bool pci_endpoint_test_bar(struct pci_endpoint_test *test,
>	if (!read_buf)
>		return false;
>
> -	iters = bar_size / buf_size;
> +	remain = do_div(bar_size, buf_size);
> +	iters = bar_size;
>	for (j = 0; j < iters; j++)
>		if (pci_endpoint_test_bar_memcmp(test, barno, buf_size * j,
>						 write_buf, read_buf, buf_size))
>			return false;
>
> -	remain = bar_size % buf_size;
>	if (remain)
>		if (pci_endpoint_test_bar_memcmp(test, barno, buf_size * iters,
>						 write_buf, read_buf, remain))
>
> base-commit: ccb98ccef0e543c2bd4ef1a72270461957f3d8d0
> --
> 2.25.1
>

Changes themselves look good to me.


Kind regards,
Niklas