Do not intent to access the vring MemoryRegion cache if the queue is not ready (no vring available).
This fixes issue #301: qemu-system-i386: include/exec/memory_ldst_cached.h.inc:77: void address_space_stw_le_cached(MemoryRegionCache *, hwaddr, uint16_t, MemTxAttrs, MemTxResult *): Assertion `addr < cache->len && 2 <= cache->len - addr' failed. Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted. (gdb) bt #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6 #4 0x0000555558f2a122 in address_space_stw_le_cached (cache=0x61300010bb70, addr=516, val=0, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:77 #5 0x0000555558f2964c in stw_le_phys_cached (cache=0x61300010bb70, addr=516, val=0) at include/exec/memory_ldst_phys.h.inc:109 #6 0x0000555558f28da8 in virtio_stw_phys_cached (vdev=0x62d00004e680, cache=0x61300010bb70, pa=516, value=0) at include/hw/virtio/virtio-access.h:196 #7 0x0000555558f287dc in vring_set_avail_event (vq=0x7fff5d23e800, val=0) at hw/virtio/virtio.c:428 #8 0x0000555558efabb7 in virtio_queue_split_set_notification (vq=0x7fff5d23e800, enable=1) at hw/virtio/virtio.c:437 #9 0x0000555558ef9f3c in virtio_queue_set_notification (vq=0x7fff5d23e800, enable=1) at hw/virtio/virtio.c:498 #10 0x0000555558c94786 in virtio_blk_handle_vq (s=0x62d00004e680, vq=0x7fff5d23e800) at hw/block/virtio-blk.c:795 #11 0x0000555558cb96c2 in virtio_blk_data_plane_handle_output (vdev=0x62d00004e680, vq=0x7fff5d23e800) at hw/block/dataplane/virtio-blk.c:165 #12 0x0000555558f35937 in virtio_queue_notify_aio_vq (vq=0x7fff5d23e800) at hw/virtio/virtio.c:2323 #13 0x0000555558f264b3 in virtio_queue_host_notifier_aio_read (n=0x7fff5d23e87c) at hw/virtio/virtio.c:3532 #14 0x0000555559a9cd3e in aio_dispatch_handler (ctx=0x613000063000, node=0x60d000008f40) at util/aio-posix.c:329 #15 0x0000555559a963ae in aio_dispatch_handlers (ctx=0x613000063000) at util/aio-posix.c:372 #16 0x0000555559a95f82 in aio_dispatch (ctx=0x613000063000) at util/aio-posix.c:382 and #302: qemu-system-i386: include/exec/memory_ldst_cached.h.inc:30: uint16_t address_space_lduw_le_cached(MemoryRegionCache *, hwaddr, MemTxAttrs, MemTxResult *): Assertion `addr < cache->len && 2 <= cache->len - addr' failed. Thread 1 "qemu-system-i38" received signal SIGABRT, Aborted. 0x00007ffff4d312a2 in raise () from /lib64/libc.so.6 (gdb) bt #1 0x00007ffff4d1a8a4 in abort () at /lib64/libc.so.6 #4 0x0000555558f2b8ec in address_space_lduw_le_cached (cache=0x61300010a7c0, addr=134, attrs=..., result=0x0) at include/exec/memory_ldst_cached.h.inc:30 #5 0x0000555558f2ac6b in lduw_le_phys_cached (cache=0x61300010a7c0, addr=134) at include/exec/memory_ldst_phys.h.inc:67 #6 0x0000555558f2a3cd in virtio_lduw_phys_cached (vdev=0x62d00003a680, cache=0x61300010a7c0, pa=134) at include/hw/virtio/virtio-access.h:166 #7 0x0000555558f300ea in vring_avail_ring (vq=0x7fffdd55d8a0, i=65) at hw/virtio/virtio.c:326 #8 0x0000555558f33b10 in vring_get_used_event (vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:332 #9 0x0000555558f33677 in virtio_split_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2471 #10 0x0000555558f1859f in virtio_should_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2523 #11 0x0000555558f188cc in virtio_notify (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/virtio/virtio.c:2565 #12 0x0000555557c2bd52 in virtio_input_handle_sts (vdev=0x62d00003a680, vq=0x7fffdd55d8a0) at hw/input/virtio-input.c:100 #13 0x0000555558f16df7 in virtio_queue_notify (vdev=0x62d00003a680, n=1) at hw/virtio/virtio.c:2363 #14 0x00005555583f45c0 in virtio_pci_notify_write (opaque=0x62d000032400, addr=7, val=0, size=1) at hw/virtio/virtio-pci.c:1369 #15 0x0000555558b80b04 in memory_region_write_accessor (mr=0x62d000033190, addr=7, value=0x7fffffff8eb0, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:492 Reported-by: Cheolwoo Myung <cwmy...@snu.ac.kr> Reported-by: Qiuhao Li <qiuhao...@outlook.com> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/301 BugLink: https://bugs.launchpad.net/qemu/+bug/1910941 Resolves: https://gitlab.com/qemu-project/qemu/-/issues/302 BugLink: https://bugs.launchpad.net/qemu/+bug/1913510 Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com> --- Could be more readable to use virtio_queue_ready() RFC because I have no clue about this hot path code, I simply looked at the backtraces. --- hw/virtio/virtio.c | 82 +++++++++++++++++++++++++++++++++++++--------- 1 file changed, 66 insertions(+), 16 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 874377f37a7..be1ec9e05ef 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -289,26 +289,38 @@ static VRingMemoryRegionCaches *vring_get_region_caches(struct VirtQueue *vq) /* Called within rcu_read_lock(). */ static inline uint16_t vring_avail_flags(VirtQueue *vq) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - hwaddr pa = offsetof(VRingAvail, flags); + VRingMemoryRegionCaches *caches; + hwaddr pa; + if (unlikely(!vq->vring.avail)) { + return 0; + } + + caches = vring_get_region_caches(vq); if (!caches) { return 0; } + pa = offsetof(VRingAvail, flags); return virtio_lduw_phys_cached(vq->vdev, &caches->avail, pa); } /* Called within rcu_read_lock(). */ static inline uint16_t vring_avail_idx(VirtQueue *vq) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - hwaddr pa = offsetof(VRingAvail, idx); + VRingMemoryRegionCaches *caches; + hwaddr pa; + if (unlikely(!vq->vring.avail)) { + return 0; + } + + caches = vring_get_region_caches(vq); if (!caches) { return 0; } + pa = offsetof(VRingAvail, idx); vq->shadow_avail_idx = virtio_lduw_phys_cached(vq->vdev, &caches->avail, pa); return vq->shadow_avail_idx; } @@ -316,13 +328,19 @@ static inline uint16_t vring_avail_idx(VirtQueue *vq) /* Called within rcu_read_lock(). */ static inline uint16_t vring_avail_ring(VirtQueue *vq, int i) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - hwaddr pa = offsetof(VRingAvail, ring[i]); + VRingMemoryRegionCaches *caches; + hwaddr pa; + if (unlikely(!vq->vring.avail)) { + return 0; + } + + caches = vring_get_region_caches(vq); if (!caches) { return 0; } + pa = offsetof(VRingAvail, ring[i]); return virtio_lduw_phys_cached(vq->vdev, &caches->avail, pa); } @@ -336,13 +354,19 @@ static inline uint16_t vring_get_used_event(VirtQueue *vq) static inline void vring_used_write(VirtQueue *vq, VRingUsedElem *uelem, int i) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - hwaddr pa = offsetof(VRingUsed, ring[i]); + VRingMemoryRegionCaches *caches; + hwaddr pa; + if (unlikely(!vq->vring.avail)) { + return; + } + + caches = vring_get_region_caches(vq); if (!caches) { return; } + pa = offsetof(VRingUsed, ring[i]); virtio_tswap32s(vq->vdev, &uelem->id); virtio_tswap32s(vq->vdev, &uelem->len); address_space_write_cached(&caches->used, pa, uelem, sizeof(VRingUsedElem)); @@ -352,23 +376,35 @@ static inline void vring_used_write(VirtQueue *vq, VRingUsedElem *uelem, /* Called within rcu_read_lock(). */ static uint16_t vring_used_idx(VirtQueue *vq) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - hwaddr pa = offsetof(VRingUsed, idx); + VRingMemoryRegionCaches *caches; + hwaddr pa; + if (unlikely(!vq->vring.avail)) { + return 0; + } + + caches = vring_get_region_caches(vq); if (!caches) { return 0; } + pa = offsetof(VRingUsed, idx); return virtio_lduw_phys_cached(vq->vdev, &caches->used, pa); } /* Called within rcu_read_lock(). */ static inline void vring_used_idx_set(VirtQueue *vq, uint16_t val) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - hwaddr pa = offsetof(VRingUsed, idx); + VRingMemoryRegionCaches *caches; + if (unlikely(!vq->vring.avail)) { + return; + } + + caches = vring_get_region_caches(vq); if (caches) { + hwaddr pa = offsetof(VRingUsed, idx); + virtio_stw_phys_cached(vq->vdev, &caches->used, pa, val); address_space_cache_invalidate(&caches->used, pa, sizeof(val)); } @@ -379,17 +415,22 @@ static inline void vring_used_idx_set(VirtQueue *vq, uint16_t val) /* Called within rcu_read_lock(). */ static inline void vring_used_flags_set_bit(VirtQueue *vq, int mask) { - VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); - VirtIODevice *vdev = vq->vdev; - hwaddr pa = offsetof(VRingUsed, flags); + VRingMemoryRegionCaches *caches; + hwaddr pa; uint16_t flags; + if (unlikely(!vq->vring.avail)) { + return; + } + + caches = vring_get_region_caches(vq); if (!caches) { return; } + pa = offsetof(VRingUsed, flags); flags = virtio_lduw_phys_cached(vq->vdev, &caches->used, pa); - virtio_stw_phys_cached(vdev, &caches->used, pa, flags | mask); + virtio_stw_phys_cached(vq->vdev, &caches->used, pa, flags | mask); address_space_cache_invalidate(&caches->used, pa, sizeof(flags)); } @@ -401,6 +442,10 @@ static inline void vring_used_flags_unset_bit(VirtQueue *vq, int mask) hwaddr pa = offsetof(VRingUsed, flags); uint16_t flags; + if (unlikely(!vq->vring.avail)) { + return; + } + if (!caches) { return; } @@ -415,10 +460,15 @@ static inline void vring_set_avail_event(VirtQueue *vq, uint16_t val) { VRingMemoryRegionCaches *caches; hwaddr pa; + if (!vq->notification) { return; } + if (unlikely(!vq->vring.avail)) { + return; + } + caches = vring_get_region_caches(vq); if (!caches) { return; -- 2.31.1
