6.10-stable review patch. If anyone has any objections, please let me know.
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From: Joao Martins joao.m.martins@oracle.com
[ Upstream commit 9560393b830b415b2151b3dd8e065257cccbffa7 ]
The calculation returns 0 if it sets less than the number of bits per byte. For calculating memory allocation from bits, lets round it up to one byte.
Link: https://lore.kernel.org/r/20240627110105.62325-3-joao.m.martins@oracle.com Reported-by: Matt Ochs mochs@nvidia.com Fixes: a9af47e382a4 ("iommufd/selftest: Test IOMMU_HWPT_GET_DIRTY_BITMAP") Signed-off-by: Joao Martins joao.m.martins@oracle.com Reviewed-by: Kevin Tian kevin.tian@intel.com Tested-by: Matt Ochs mochs@nvidia.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/iommufd/selftest.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c index 7a2199470f312..654ed33390957 100644 --- a/drivers/iommu/iommufd/selftest.c +++ b/drivers/iommu/iommufd/selftest.c @@ -1334,7 +1334,7 @@ static int iommufd_test_dirty(struct iommufd_ucmd *ucmd, unsigned int mockpt_id, }
max = length / page_size; - bitmap_size = max / BITS_PER_BYTE; + bitmap_size = DIV_ROUND_UP(max, BITS_PER_BYTE);
tmp = kvzalloc(bitmap_size, GFP_KERNEL_ACCOUNT); if (!tmp) {