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-rw-r--r--test/syscalls/linux/fpsig_nested.cc134
1 files changed, 0 insertions, 134 deletions
diff --git a/test/syscalls/linux/fpsig_nested.cc b/test/syscalls/linux/fpsig_nested.cc
deleted file mode 100644
index c476a8e7a..000000000
--- a/test/syscalls/linux/fpsig_nested.cc
+++ /dev/null
@@ -1,134 +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 program verifies that application floating point state is restored
-// correctly after a signal handler returns. It also verifies that this works
-// with nested signals.
-#include <sys/time.h>
-
-#include "gtest/gtest.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 pid;
-int tid;
-
-volatile uint64_t entryxmm[2] = {~0UL, ~0UL};
-volatile uint64_t exitxmm[2];
-
-void sigusr2(int s, siginfo_t* siginfo, void* _uc) {
- uint64_t val = SIGUSR2;
-
- // Record the value of %xmm0 on entry and then clobber it.
- GET_XMM(entryxmm[1], xmm0);
- SET_XMM(val, xmm0);
- GET_XMM(exitxmm[1], xmm0);
-}
-
-void sigusr1(int s, siginfo_t* siginfo, void* _uc) {
- uint64_t val = SIGUSR1;
-
- // Record the value of %xmm0 on entry and then clobber it.
- GET_XMM(entryxmm[0], xmm0);
- SET_XMM(val, xmm0);
-
- // Send a SIGUSR2 to ourself. The signal mask is configured such that
- // the SIGUSR2 handler will run before this handler returns.
- asm volatile(
- "movl %[killnr], %%eax;"
- "movl %[pid], %%edi;"
- "movl %[tid], %%esi;"
- "movl %[sig], %%edx;"
- "syscall;"
- :
- : [ killnr ] "i"(__NR_tgkill), [ pid ] "rm"(pid), [ tid ] "rm"(tid),
- [ sig ] "i"(SIGUSR2)
- : "rax", "rdi", "rsi", "rdx",
- // Clobbered by syscall.
- "rcx", "r11");
-
- // Record value of %xmm0 again to verify that the nested signal handler
- // does not clobber it.
- GET_XMM(exitxmm[0], xmm0);
-}
-
-TEST(FPSigTest, NestedSignals) {
- pid = getpid();
- 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());
-
- sa.sa_sigaction = sigusr2;
- ASSERT_THAT(sigaction(SIGUSR2, &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 signal, using tgkill
- // to signal the current thread ensures that this is the clobbered thread.
-
- uint64_t expected = 0xdeadbeeffacefeed;
- SET_XMM(expected, xmm0);
-
- asm volatile(
- "movl %[killnr], %%eax;"
- "movl %[pid], %%edi;"
- "movl %[tid], %%esi;"
- "movl %[sig], %%edx;"
- "syscall;"
- :
- : [ killnr ] "i"(__NR_tgkill), [ pid ] "rm"(pid), [ tid ] "rm"(tid),
- [ sig ] "i"(SIGUSR1)
- : "rax", "rdi", "rsi", "rdx",
- // Clobbered by syscall.
- "rcx", "r11");
-
- uint64_t got;
- GET_XMM(got, xmm0);
-
- //
- // The checks below verifies the following:
- // - signal handlers must called with a clean fpu state.
- // - sigreturn(2) must restore fpstate of the interrupted context.
- //
- EXPECT_EQ(expected, got);
- EXPECT_EQ(entryxmm[0], 0);
- EXPECT_EQ(entryxmm[1], 0);
- EXPECT_EQ(exitxmm[0], SIGUSR1);
- EXPECT_EQ(exitxmm[1], SIGUSR2);
-}
-
-} // namespace
-
-} // namespace testing
-} // namespace gvisor