kernel/linux.git/net/xdp/xsk_queue.c, branch v7.0.10

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

xdp: Fix zero-size allocation warning in xskq_create()

2023-10-09T14:13:29+00:00

Syzkaller reported the following issue: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 2807 at mm/vmalloc.c:3247 __vmalloc_node_range (mm/vmalloc.c:3361) Modules linked in: CPU: 0 PID: 2807 Comm: repro Not tainted 6.6.0-rc2+ #12 Hardware name: Generic DT based system unwind_backtrace from show_stack (arch/arm/kernel/traps.c:258) show_stack from dump_stack_lvl (lib/dump_stack.c:107 (discriminator 1)) dump_stack_lvl from __warn (kernel/panic.c:633 kernel/panic.c:680) __warn from warn_slowpath_fmt (./include/linux/context_tracking.h:153 kernel/panic.c:700) warn_slowpath_fmt from __vmalloc_node_range (mm/vmalloc.c:3361 (discriminator 3)) __vmalloc_node_range from vmalloc_user (mm/vmalloc.c:3478) vmalloc_user from xskq_create (net/xdp/xsk_queue.c:40) xskq_create from xsk_setsockopt (net/xdp/xsk.c:953 net/xdp/xsk.c:1286) xsk_setsockopt from __sys_setsockopt (net/socket.c:2308) __sys_setsockopt from ret_fast_syscall (arch/arm/kernel/entry-common.S:68) xskq_get_ring_size() uses struct_size() macro to safely calculate the size of struct xsk_queue and q->nentries of desc members. But the syzkaller repro was able to set q->nentries with the value initially taken from copy_from_sockptr() high enough to return SIZE_MAX by struct_size(). The next PAGE_ALIGN(size) is such case will overflow the size_t value and set it to 0. This will trigger WARN_ON_ONCE in vmalloc_user() -> __vmalloc_node_range(). The issue is reproducible on 32-bit arm kernel. Fixes: 9f78bf330a66 ("xsk: support use vaddr as ring") Reported-by: syzbot+fae676d3cf469331fc89@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/000000000000c84b4705fb31741e@google.com/T/ Reported-by: syzbot+b132693e925cbbd89e26@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/000000000000e20df20606ebab4f@google.com/T/ Signed-off-by: Andrew Kanner Signed-off-by: Daniel Borkmann Tested-by: syzbot+fae676d3cf469331fc89@syzkaller.appspotmail.com Acked-by: Magnus Karlsson Link: https://syzkaller.appspot.com/bug?extid=fae676d3cf469331fc89 Link: https://lore.kernel.org/bpf/20231007075148.1759-1-andrew.kanner@gmail.com

xsk: support use vaddr as ring

2023-02-20T08:22:12+00:00

When we try to start AF_XDP on some machines with long running time, due to the machine's memory fragmentation problem, there is no sufficient contiguous physical memory that will cause the start failure. If the size of the queue is 8 * 1024, then the size of the desc[] is 8 * 1024 * 8 = 16 * PAGE, but we also add struct xdp_ring size, so it is 16page+. This is necessary to apply for a 4-order memory. If there are a lot of queues, it is difficult to these machine with long running time. Here, that we actually waste 15 pages. 4-Order memory is 32 pages, but we only use 17 pages. This patch replaces __get_free_pages() by vmalloc() to allocate memory to solve these problems. Signed-off-by: Xuan Zhuo Acked-by: Magnus Karlsson Reviewed-by: Alexander Lobakin Signed-off-by: David S. Miller

xsk: Remove MEM_TYPE_ZERO_COPY and corresponding code

2020-05-22T00:31:27+00:00

There are no users of MEM_TYPE_ZERO_COPY. Remove all corresponding code, including the "handle" member of struct xdp_buff. rfc->v1: Fixed spelling in commit message. (Björn) Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200520192103.355233-13-bjorn.topel@gmail.com

xsk: Move driver interface to xdp_sock_drv.h

2020-05-22T00:31:26+00:00

Move the AF_XDP zero-copy driver interface to its own include file called xdp_sock_drv.h. This, hopefully, will make it more clear for NIC driver implementors to know what functions to use for zero-copy support. v4->v5: Fix -Wmissing-prototypes by include header file. (Jakub) Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200520192103.355233-4-bjorn.topel@gmail.com

xsk: Change two variable names for increased clarity

2020-05-04T20:56:26+00:00

Change two variables names so that it is clearer what they represent. The first one is xsk_list that in fact only contains the list of AF_XDP sockets with a Tx component. Change this to xsk_tx_list for improved clarity. The second variable is size in the ring structure. One might think that this is the size of the ring, but it is in fact the size of the umem, copied into the ring structure to improve performance. Rename this variable umem_size to avoid any confusion. Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann Acked-by: Jonathan Lemon Link: https://lore.kernel.org/bpf/1588599232-24897-2-git-send-email-magnus.karlsson@intel.com

xsk: Use struct_size() helper

2019-12-21T00:00:09+00:00

Improve readability and maintainability by using the struct_size() helper when allocating the AF_XDP rings. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/1576759171-28550-13-git-send-email-magnus.karlsson@intel.com

net: xsk: add a simple buffer reuse queue

2018-09-25T20:13:15+00:00

XSK UMEM is strongly single producer single consumer so reuse of frames is challenging. Add a simple "stash" of FILL packets to reuse for drivers to optionally make use of. This is useful when driver has to free (ndo_stop) or resize a ring with an active AF_XDP ZC socket. Signed-off-by: Jakub Kicinski Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher

xsk: i40e: get rid of useless struct xdp_umem_props

2018-08-31T23:38:16+00:00

This commit gets rid of the structure xdp_umem_props. It was there to be able to break a dependency at one point, but this is no longer needed. The values in the struct are instead stored directly in the xdp_umem structure. This simplifies the xsk code as well as af_xdp zero-copy drivers and as a bonus gets rid of one internal header file. The i40e driver is also adapted to the new interface in this commit. Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann