blaster4385/linux-IllusionX/drivers/virtio/virtio_ring.c, branch v6.12.10

virtio_ring: add a func argument 'recycle_done' to virtqueue_resize()

2024-12-19T17:12:59Z

commit 8d6712c892019b9b9dc5c7039edd3c9d770b510b upstream. When virtqueue_resize() has actually recycled all unused buffers, additional work may be required in some cases. Relying solely on its return status is fragile, so introduce a new function argument 'recycle_done', which is invoked when the recycle really occurs. Cc: # v6.11+ Signed-off-by: Koichiro Den Acked-by: Jason Wang Reviewed-by: Xuan Zhuo Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

virtio_ring: tag event_triggered as racy for KCSAN

2024-09-25T11:07:44Z

Setting event_triggered from the interrupt handler is fundamentally racy. There are races of 2 types: 1. vq processing can read false value while interrupt triggered and set it to true. result will be a bit of extra work when disabling cbs, no big deal. 1. vq processing can set false value then interrupt immediately sets true value since interrupt then triggers a callback which will process buffers, this is also not an issue. However, looks like KCSAN can not figure all this out, and warns about the race between the write and the read. Tag the access data_racy for now. We should probably look at ways to make this more straight-forwardly correct. Message-ID: <6bdd771a4fb7625a9227971b3cf4745c34c31a32.1726153334.git.mst@redhat.com> Reported-by: syzbot+8a02104389c2e0ef5049@syzkaller.appspotmail.com Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Acked-by: Marco Elver

virtio: add missing MODULE_DESCRIPTION() macros

2024-07-09T12:42:41Z

With ARCH=sh, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/virtio/virtio.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/virtio/virtio_ring.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson Message-Id: <20240702-md-sh-drivers-virtio-v1-1-cf7325ab6ccc@quicinc.com> Signed-off-by: Michael S. Tsirkin

virtio_ring: fix KMSAN error for premapped mode

2024-07-04T15:00:31Z

Add kmsan for virtqueue_dma_map_single_attrs to fix: BUG: KMSAN: uninit-value in receive_buf+0x45ca/0x6990 receive_buf+0x45ca/0x6990 virtnet_poll+0x17e0/0x3130 net_rx_action+0x832/0x26e0 handle_softirqs+0x330/0x10f0 [...] Uninit was created at: __alloc_pages_noprof+0x62a/0xe60 alloc_pages_noprof+0x392/0x830 skb_page_frag_refill+0x21a/0x5c0 virtnet_rq_alloc+0x50/0x1500 try_fill_recv+0x372/0x54c0 virtnet_open+0x210/0xbe0 __dev_open+0x56e/0x920 __dev_change_flags+0x39c/0x2000 dev_change_flags+0xaa/0x200 do_setlink+0x197a/0x7420 rtnl_setlink+0x77c/0x860 [...] Signed-off-by: Xuan Zhuo Tested-by: Alexander Potapenko Message-Id: <20240606111345.93600-1-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin Tested-by: Ilya Leoshkevich # s390x Acked-by: Jason Wang

virtio_ring: enable premapped mode whatever use_dma_api

2024-05-14T00:07:41Z

Now, we have virtio DMA APIs, the driver can be the premapped mode whatever the virtio core uses dma api or not. So remove the limit of checking use_dma_api from virtqueue_set_dma_premapped(). Signed-off-by: Xuan Zhuo Acked-by: Jason Wang Link: https://lore.kernel.org/r/20240511031404.30903-2-xuanzhuo@linux.alibaba.com Signed-off-by: Jakub Kicinski

virtio: packed: fix unmap leak for indirect desc table

2024-03-19T07:19:22Z

When use_dma_api and premapped are true, then the do_unmap is false. Because the do_unmap is false, vring_unmap_extra_packed is not called by detach_buf_packed. if (unlikely(vq->do_unmap)) { curr = id; for (i = 0; i < state->num; i++) { vring_unmap_extra_packed(vq, &vq->packed.desc_extra[curr]); curr = vq->packed.desc_extra[curr].next; } } So the indirect desc table is not unmapped. This causes the unmap leak. So here, we check vq->use_dma_api instead. Synchronously, dma info is updated based on use_dma_api judgment This bug does not occur, because no driver use the premapped with indirect. Fixes: b319940f83c2 ("virtio_ring: skip unmap for premapped") Signed-off-by: Xuan Zhuo Message-Id: <20240223071833.26095-1-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin

virtio_ring: fix syncs DMA memory with different direction

2023-12-04T13:36:25Z

Now the APIs virtqueue_dma_sync_single_range_for_{cpu,device} ignore the parameter 'dir', that is a mistake. [ 6.101666] ------------[ cut here ]------------ [ 6.102079] DMA-API: virtio-pci 0000:00:04.0: device driver syncs DMA memory with different direction [device address=0x00000000ae010000] [size=32752 bytes] [mapped with DMA_FROM_DEVICE] [synced with DMA_BIDIRECTIONAL] [ 6.103630] WARNING: CPU: 6 PID: 0 at kernel/dma/debug.c:1125 check_sync+0x53e/0x6c0 [ 6.107420] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G E 6.6.0+ #290 [ 6.108030] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 6.108936] RIP: 0010:check_sync+0x53e/0x6c0 [ 6.109289] Code: 24 10 e8 f5 d9 74 00 4c 8b 4c 24 10 4c 8b 44 24 18 48 8b 4c 24 20 48 89 c6 41 56 4c 89 ea 48 c7 c7 b0 f1 50 82 e8 32 fc f3 ff <0f> 0b 48 c7 c7 48 4b 4a 82 e8 74 d9 fc ff 8b 73 4c 48 8d 7b 50 31 [ 6.110750] RSP: 0018:ffffc90000180cd8 EFLAGS: 00010092 [ 6.111178] RAX: 00000000000000ce RBX: ffff888100aa5900 RCX: 0000000000000000 [ 6.111744] RDX: 0000000000000104 RSI: ffffffff824c3208 RDI: 00000000ffffffff [ 6.112316] RBP: ffffc90000180d40 R08: 0000000000000000 R09: 00000000fffeffff [ 6.112893] R10: ffffc90000180b98 R11: ffffffff82f63308 R12: ffffffff83d5af00 [ 6.113460] R13: ffff888100998200 R14: ffffffff824a4b5f R15: 0000000000000286 [ 6.114027] FS: 0000000000000000(0000) GS:ffff88842fd80000(0000) knlGS:0000000000000000 [ 6.114665] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6.115128] CR2: 00007f10f1e03030 CR3: 0000000108272004 CR4: 0000000000770ee0 [ 6.115701] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 6.116272] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 6.116842] PKRU: 55555554 [ 6.117069] Call Trace: [ 6.117275] [ 6.117452] ? __warn+0x84/0x140 [ 6.117727] ? check_sync+0x53e/0x6c0 [ 6.118034] ? __report_bug+0xea/0x100 [ 6.118353] ? check_sync+0x53e/0x6c0 [ 6.118653] ? report_bug+0x41/0xc0 [ 6.118944] ? handle_bug+0x3c/0x70 [ 6.119237] ? exc_invalid_op+0x18/0x70 [ 6.119551] ? asm_exc_invalid_op+0x1a/0x20 [ 6.119900] ? check_sync+0x53e/0x6c0 [ 6.120199] ? check_sync+0x53e/0x6c0 [ 6.120499] debug_dma_sync_single_for_cpu+0x5c/0x70 [ 6.120906] ? dma_sync_single_for_cpu+0xb7/0x100 [ 6.121291] virtnet_rq_unmap+0x158/0x170 [virtio_net] [ 6.121716] virtnet_receive+0x196/0x220 [virtio_net] [ 6.122135] virtnet_poll+0x48/0x1b0 [virtio_net] [ 6.122524] __napi_poll+0x29/0x1b0 [ 6.123083] net_rx_action+0x282/0x360 [ 6.123612] __do_softirq+0xf3/0x2fb [ 6.124138] __irq_exit_rcu+0x8e/0xf0 [ 6.124663] common_interrupt+0xbc/0xe0 [ 6.125202] We need to enable CONFIG_DMA_API_DEBUG and work with need sync mode(such as swiotlb) to reproduce this warn. Fixes: 8bd2f71054bd ("virtio_ring: introduce dma sync api for virtqueue") Reported-by: "Ning, Hongyu" Closes: https://lore.kernel.org/all/f37cb55a-6fc8-4e21-8789-46d468325eea@linux.intel.com/ Suggested-by: Jason Wang Signed-off-by: Xuan Zhuo Message-Id: <20231201033303.25141-1-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Parav Pandit Acked-by: Jason Wang Tested-by: Hongyu Ning

virtio_ring: fix avail_wrap_counter in virtqueue_add_packed

2023-09-03T22:10:24Z

In current packed virtqueue implementation, the avail_wrap_counter won't flip, in the case when the driver supplies a descriptor chain with a length equals to the queue size; total_sg == vq->packed.vring.num. Let’s assume the following situation: vq->packed.vring.num=4 vq->packed.next_avail_idx: 1 vq->packed.avail_wrap_counter: 0 Then the driver adds a descriptor chain containing 4 descriptors. We expect the following result with avail_wrap_counter flipped: vq->packed.next_avail_idx: 1 vq->packed.avail_wrap_counter: 1 But, the current implementation gives the following result: vq->packed.next_avail_idx: 1 vq->packed.avail_wrap_counter: 0 To reproduce the bug, you can set a packed queue size as small as possible, so that the driver is more likely to provide a descriptor chain with a length equal to the packed queue size. For example, in qemu run following commands: sudo qemu-system-x86_64 \ -enable-kvm \ -nographic \ -kernel "path/to/kernel_image" \ -m 1G \ -drive file="path/to/rootfs",if=none,id=disk \ -device virtio-blk,drive=disk \ -drive file="path/to/disk_image",if=none,id=rwdisk \ -device virtio-blk,drive=rwdisk,packed=on,queue-size=4,\ indirect_desc=off \ -append "console=ttyS0 root=/dev/vda rw init=/bin/bash" Inside the VM, create a directory and mount the rwdisk device on it. The rwdisk will hang and mount operation will not complete. This commit fixes the wrap counter error by flipping the packed.avail_wrap_counter, when start of descriptor chain equals to the end of descriptor chain (head == i). Fixes: 1ce9e6055fa0 ("virtio_ring: introduce packed ring support") Signed-off-by: Yuan Yao Message-Id: <20230808051110.3492693-1-yuanyaogoog@chromium.org> Acked-by: Jason Wang Signed-off-by: Michael S. Tsirkin

virtio_ring: introduce dma sync api for virtqueue

2023-09-03T22:10:23Z

These API has been introduced: * virtqueue_dma_need_sync * virtqueue_dma_sync_single_range_for_cpu * virtqueue_dma_sync_single_range_for_device These APIs can be used together with the premapped mechanism to sync the DMA address. Signed-off-by: Xuan Zhuo Message-Id: <20230810123057.43407-12-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin

virtio_ring: introduce dma map api for virtqueue

2023-09-03T22:10:23Z

Added virtqueue_dma_map_api* to map DMA addresses for virtual memory in advance. The purpose is to keep memory mapped across multiple add/get buf operations. Signed-off-by: Xuan Zhuo Message-Id: <20230810123057.43407-11-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin