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15126cba86
Sets valid.max_access_size and valid.min_access_size to ensure safe 8-byte accesses to vfio. Today, 8-byte accesses are broken into pairs of 4-byte calls that goes unprotected: qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc0, 0x2020c, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc4, 0xa0000, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 which occasionally leads to: qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc0, 0x2030c, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc0, 0x1000c, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc4, 0xb0000, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc4, 0xa0000, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 causing strange errors in guest OS. With this patch, such accesses are protected by the same lock guard: qemu_mutex_lock locked mutex 0x10905ad8 vfio_region_write (0001:03:00.0:region1+0xc0, 0x2000c, 4) vfio_region_write (0001:03:00.0:region1+0xc4, 0xb0000, 4) qemu_mutex_unlock unlocked mutex 0x10905ad8 This happens because the 8-byte write should be broken into 4-byte writes by memory.c:access_with_adjusted_size() in order to be under the same lock. Today, it's done in exec.c:address_space_write_continue() which was able to handle only 4 bytes due to a zero'ed valid.max_access_size (see exec.c:memory_access_size()). Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> |
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| .. | ||
| amd-xgbe.c | ||
| calxeda-xgmac.c | ||
| common.c | ||
| Makefile.objs | ||
| pci-quirks.c | ||
| pci.c | ||
| pci.h | ||
| platform.c | ||
| spapr.c | ||
| trace-events | ||