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alistair23-linux/tools/testing
Vitaly Kuznetsov ef40598098 selftests: kvm: fix sync_regs_test with newer gccs
Commit 204c91eff7 ("KVM: selftests: do not blindly clobber registers in
 guest asm") was intended to make test more gcc-proof, however, the result
is exactly the opposite: on newer gccs (e.g. 8.2.1) the test breaks with

==== Test Assertion Failure ====
  x86_64/sync_regs_test.c:168: run->s.regs.regs.rbx == 0xBAD1DEA + 1
  pid=14170 tid=14170 - Invalid argument
     1	0x00000000004015b3: main at sync_regs_test.c:166 (discriminator 6)
     2	0x00007f413fb66412: ?? ??:0
     3	0x000000000040191d: _start at ??:?
  rbx sync regs value incorrect 0x1.

Apparently, compile is still free to play games with registers even
when they have variables attached.

Re-write guest code with 'asm volatile' by embedding ucall there and
making sure rbx is preserved.

Fixes: 204c91eff7 ("KVM: selftests: do not blindly clobber registers in guest asm")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-10-22 13:31:18 +02:00
..
fault-injection docs: fault-injection: convert docs to ReST and rename to *.rst 2019-06-14 14:21:07 -06:00
ktest ktest: Fix some typos in config-bisect.pl 2019-07-24 15:37:18 -04:00
nvdimm libnvdimm fixes v5.4-rc1 2019-09-29 10:33:41 -07:00
radix-tree Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 15:45:14 -07:00
scatterlist treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
selftests selftests: kvm: fix sync_regs_test with newer gccs 2019-10-22 13:31:18 +02:00
vsock treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00