dcafa24827
Found this when I wanted to try the per-vcpu dirty rate series out, then I found that it's not really working and it can quickly hang death a guest. I found strange errors (e.g. guest crash after migration) happens even without the per-vcpu dirty rate series. When merging dirty ring, probably no one notice that the trivial renaming diff [1] missed two existing references of kvm_dirty_ring_sizes; they do matter since otherwise we'll mmap() a shorter range of memory after the renaming. I think it didn't SIGBUS for me easily simply because some other stuff within qemu mmap()ed right after the dirty rings (e.g. when testing 4096 slots, it aligned with one small page on x86), so when we access the rings we've been reading/writting to random memory elsewhere of qemu. Fix the two sizes when map/unmap the shared dirty gfn memory. [1] https://lore.kernel.org/qemu-devel/dac5f0c6-1bca-3daf-e5d2-6451dbbaca93@redhat.com/ Cc: Hyman Huang <huangy81@chinatelecom.cn> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20210609014355.217110-1-peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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| .. | ||
| kvm-accel-ops.c | ||
| kvm-all.c | ||
| kvm-cpus.h | ||
| meson.build | ||
| sev-stub.c | ||
| trace-events | ||
| trace.h | ||