@@ -500,11 +500,10 @@ calc_map_type_and_dist_warn(struct pci_dev *provider, struct pci_dev *client,
{
struct seq_buf acs_list;
bool acs_redirects;
+ char buf[128];
int ret;
- seq_buf_init(&acs_list, kmalloc(PAGE_SIZE, GFP_KERNEL), PAGE_SIZE);
- if (!acs_list.buffer)
- return -ENOMEM;
+ seq_buf_init(&acs_list, buf, sizeof(buf));
ret = calc_map_type_and_dist(provider, client, dist, &acs_redirects,
&acs_list);
@@ -522,8 +521,6 @@ calc_map_type_and_dist_warn(struct pci_dev *provider, struct pci_dev *client,
pci_name(provider));
}
- kfree(acs_list.buffer);
-
return ret;
}
In order to call the calc_map_type_and_dist_warn() function from a dma_map operation, the function must not sleep. The only reason it sleeps is to allocate memory for the seq_buf to print a verbose warning telling the user how to disable ACS for that path. Instead of allocating the memory with kmalloc, allocate it on the stack with a smaller buffer. A 128B buffer is enough to print 10 pci device names. A system with 10 bridge ports between two devices that have ACS enabled would be unusually large, so this should still be a reasonable limit. This also allows cleaning up the awkward (and broken) return with -ENOMEM which contradicts the return type and the caller was not prepared for. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> --- drivers/pci/p2pdma.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)