Re: [PATCH V4 vfio 5/7] vfio/virtio: Add support for the basic live migration functionality

[Yishai Hadas]

On 14/11/2024 1:28, Alex Williamson wrote:

On Wed, 13 Nov 2024 13:51:58 +0200
Yishai Hadas <yish...@nvidia.com> wrote:

diff --git a/drivers/vfio/pci/virtio/migrate.c 
b/drivers/vfio/pci/virtio/migrate.c
new file mode 100644
index 000000000000..a0ce3ec2c734
--- /dev/null
+++ b/drivers/vfio/pci/virtio/migrate.c

...

+static int virtiovf_add_migration_pages(struct virtiovf_data_buffer *buf,
+                                       unsigned int npages)
+{
+       unsigned int to_alloc = npages;
+       struct page **page_list;
+       unsigned long filled;
+       unsigned int to_fill;
+       int ret;
+       int i;
+
+       to_fill = min_t(unsigned int, npages, PAGE_SIZE / sizeof(*page_list));
+       page_list = kvzalloc(to_fill * sizeof(*page_list), GFP_KERNEL_ACCOUNT);

checkpatch spots the following:

WARNING: Prefer kvcalloc over kvzalloc with multiply
#416: FILE: drivers/vfio/pci/virtio/migrate.c:71:
+       page_list = kvzalloc(to_fill * sizeof(*page_list), GFP_KERNEL_ACCOUNT);


With your approval I'll update with the following on commit:

Sure, thanks.

Yishai

diff --git a/drivers/vfio/pci/virtio/migrate.c 
b/drivers/vfio/pci/virtio/migrate.c
index a0ce3ec2c734..4fdf6ca17a3a 100644
--- a/drivers/vfio/pci/virtio/migrate.c
+++ b/drivers/vfio/pci/virtio/migrate.c
@@ -68,7 +68,7 @@ static int virtiovf_add_migration_pages(struct 
virtiovf_data_buffer *buf,
        int i;

to_fill = min_t(unsigned int, npages, PAGE_SIZE / sizeof(*page_list));

-       page_list = kvzalloc(to_fill * sizeof(*page_list), GFP_KERNEL_ACCOUNT);
+       page_list = kvcalloc(to_fill, sizeof(*page_list), GFP_KERNEL_ACCOUNT);
        if (!page_list)
                return -ENOMEM;