| commit | 3a30014cfae7d4354503831e01b9ac1ef2b79b00 | |
| author | Marcelo Tosatti <mtosatti@redhat.com> | |
| Fri, 22 Aug 2008 23:03:35 +0000 (22 20:03 -0300) | ||
| committer | Avi Kivity <avi@qumranet.com> | |
| Mon, 25 Aug 2008 10:20:36 +0000 (25 13:20 +0300) | ||
| tree | f26053e0364947ce0844f61e3c1d4cfa31553622 | treesnapshot (tar.gz zip) |
| parent | bb473282dca53b93f54e77fd10923e9d43dd6293 | commitdiff |
Mark guest mapping as MADV_DONTFORK
When qemu fork's (ssh migration, qemu-nbd, slirp), the guest memory
mapping becomes shared and write-protected by parent and child, until
execve switches to a new mm.
get_user_pages with force=1 parameter will break COW during this window,
leaving stale shadow mappings that point to the previously shared page.
Fix this by madvising the range as MADV_DONTFORK, if mmu notifiers are
disabled.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
When qemu fork's (ssh migration, qemu-nbd, slirp), the guest memory
mapping becomes shared and write-protected by parent and child, until
execve switches to a new mm.
get_user_pages with force=1 parameter will break COW during this window,
leaving stale shadow mappings that point to the previously shared page.
Fix this by madvising the range as MADV_DONTFORK, if mmu notifiers are
disabled.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
| qemu-kvm.c | diffblobblamehistory | |
| qemu-kvm.h | diffblobblamehistory | |
| vl.c | diffblobblamehistory |