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-rw-r--r--test/syscalls/linux/fpsig_fork.cc105
1 files changed, 0 insertions, 105 deletions
diff --git a/test/syscalls/linux/fpsig_fork.cc b/test/syscalls/linux/fpsig_fork.cc
deleted file mode 100644
index a346f1f00..000000000
--- a/test/syscalls/linux/fpsig_fork.cc
+++ /dev/null
@@ -1,105 +0,0 @@
-// Copyright 2018 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// This test verifies that fork(2) in a signal handler will correctly
-// restore floating point state after the signal handler returns in both
-// the child and parent.
-#include <sys/time.h>
-
-#include "gtest/gtest.h"
-#include "test/util/logging.h"
-#include "test/util/test_util.h"
-#include "test/util/thread_util.h"
-
-namespace gvisor {
-namespace testing {
-
-namespace {
-
-#define GET_XMM(__var, __xmm) \
- asm volatile("movq %%" #__xmm ", %0" : "=r"(__var))
-#define SET_XMM(__var, __xmm) asm volatile("movq %0, %%" #__xmm : : "r"(__var))
-
-int parent, child;
-
-void sigusr1(int s, siginfo_t* siginfo, void* _uc) {
- // Fork and clobber %xmm0. The fpstate should be restored by sigreturn(2)
- // in both parent and child.
- child = fork();
- TEST_CHECK_MSG(child >= 0, "fork failed");
-
- uint64_t val = SIGUSR1;
- SET_XMM(val, xmm0);
-}
-
-TEST(FPSigTest, Fork) {
- parent = getpid();
- pid_t parent_tid = gettid();
-
- struct sigaction sa = {};
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = SA_SIGINFO;
- sa.sa_sigaction = sigusr1;
- ASSERT_THAT(sigaction(SIGUSR1, &sa, nullptr), SyscallSucceeds());
-
- // The amd64 ABI specifies that the XMM register set is caller-saved. This
- // implies that if there is any function call between SET_XMM and GET_XMM the
- // compiler might save/restore xmm0 implicitly. This defeats the entire
- // purpose of the test which is to verify that fpstate is restored by
- // sigreturn(2).
- //
- // This is the reason why 'tgkill(getpid(), gettid(), SIGUSR1)' is implemented
- // in inline assembly below.
- //
- // If the OS is broken and registers are clobbered by the child, using tgkill
- // to signal the current thread increases the likelihood that this thread will
- // be the one clobbered.
-
- uint64_t expected = 0xdeadbeeffacefeed;
- SET_XMM(expected, xmm0);
-
- asm volatile(
- "movl %[killnr], %%eax;"
- "movl %[parent], %%edi;"
- "movl %[tid], %%esi;"
- "movl %[sig], %%edx;"
- "syscall;"
- :
- : [ killnr ] "i"(__NR_tgkill), [ parent ] "rm"(parent),
- [ tid ] "rm"(parent_tid), [ sig ] "i"(SIGUSR1)
- : "rax", "rdi", "rsi", "rdx",
- // Clobbered by syscall.
- "rcx", "r11");
-
- uint64_t got;
- GET_XMM(got, xmm0);
-
- if (getpid() == parent) { // Parent.
- int status;
- ASSERT_THAT(waitpid(child, &status, 0), SyscallSucceedsWithValue(child));
- EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0);
- }
-
- // TEST_CHECK_MSG since this may run in the child.
- TEST_CHECK_MSG(expected == got, "Bad xmm0 value");
-
- if (getpid() != parent) { // Child.
- _exit(0);
- }
-}
-
-} // namespace
-
-} // namespace testing
-} // namespace gvisor