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Line 68: − − === Kerndat test: check presence of the bug with mmaping over 4Gb === − − As 32-bit application is restored from 64-bit CRIU, some task's properties that were filled on <code>exec()</code> are left, which is quite unusual for 32-bit task. One of the things, left from 64-bit binary is precalculated <code>mmap_base</code> which is used to find task's top/bottom address limit during <code>mmap()</code> syscall. That means that compat <code>sys_mmap()</code> may map page over 4Gb address and return 4-byte pointer to low bytes of address. Looks like no one has used compatible mmap in 64-bit binary. Results in broken mmap in restored 32-bit application, which can map vma over 4Gb. − − See [[Upstream kernel commits]], the bug is fixed in linux-next, but the kerndat criu test should be reworked to check presence of this bug, not only arch_prctl() for 32-bit vdso. − − === Issue with compat vdso helper === − Rarely it segfaults: [https://github.com/xemul/criu/issues/290 issue], [https://github.com/xemul/criu/issues/273 reproduce]. − Presumably, because of using syscall() and memcpy() from Glibc, instead of raw pie-helpers at the moment of unmapped vdso/vvar vmas. − Hard to reproduce.
→Needs to be done (TODO): kerndat check posted, vdso helper segfault fixed
== Needs to be done (TODO) ==
== Needs to be done (TODO) ==
=== List of failed tests ===
=== List of failed tests ===