util/vfio-helpers: Trace PCI I/O config accesses

We sometime get kernel panic with some devices on Aarch64
hosts. Alex Williamson suggests it might be broken PCIe
root complex. Add trace event to record the latest I/O
access before crashing. In case, assert our accesses are
aligned.

Reviewed-by: Fam Zheng <fam@euphon.net>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20201103020733.2303148-3-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
This commit is contained in:
Philippe Mathieu-Daudé 2020-11-03 03:07:28 +01:00 committed by Stefan Hajnoczi
parent a4bc212add
commit 3d87c2d943
2 changed files with 10 additions and 0 deletions

View File

@ -85,3 +85,5 @@ qemu_vfio_new_mapping(void *s, void *host, size_t size, int index, uint64_t iova
qemu_vfio_do_mapping(void *s, void *host, size_t size, uint64_t iova) "s %p host %p size 0x%zx iova 0x%"PRIx64
qemu_vfio_dma_map(void *s, void *host, size_t size, bool temporary, uint64_t *iova) "s %p host %p size 0x%zx temporary %d iova %p"
qemu_vfio_dma_unmap(void *s, void *host) "s %p host %p"
qemu_vfio_pci_read_config(void *buf, int ofs, int size, uint64_t region_ofs, uint64_t region_size) "read cfg ptr %p ofs 0x%x size 0x%x (region addr 0x%"PRIx64" size 0x%"PRIx64")"
qemu_vfio_pci_write_config(void *buf, int ofs, int size, uint64_t region_ofs, uint64_t region_size) "write cfg ptr %p ofs 0x%x size 0x%x (region addr 0x%"PRIx64" size 0x%"PRIx64")"

View File

@ -227,6 +227,10 @@ static int qemu_vfio_pci_read_config(QEMUVFIOState *s, void *buf,
{
int ret;
trace_qemu_vfio_pci_read_config(buf, ofs, size,
s->config_region_info.offset,
s->config_region_info.size);
assert(QEMU_IS_ALIGNED(s->config_region_info.offset + ofs, size));
do {
ret = pread(s->device, buf, size, s->config_region_info.offset + ofs);
} while (ret == -1 && errno == EINTR);
@ -237,6 +241,10 @@ static int qemu_vfio_pci_write_config(QEMUVFIOState *s, void *buf, int size, int
{
int ret;
trace_qemu_vfio_pci_write_config(buf, ofs, size,
s->config_region_info.offset,
s->config_region_info.size);
assert(QEMU_IS_ALIGNED(s->config_region_info.offset + ofs, size));
do {
ret = pwrite(s->device, buf, size, s->config_region_info.offset + ofs);
} while (ret == -1 && errno == EINTR);