From 228168cbb7cc40bfb1621b0b6868c018b522276a Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 11 Jun 2021 23:08:28 -0700 Subject: [PATCH 1/9] linux-user: Set CF_PARALLEL when mapping shared memory MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signal the translator to use host atomic instructions for guest operations, insofar as it is possible. This is the best we can do to allow the guest to interact atomically with other processes. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/121 Signed-off-by: Richard Henderson Reviewed-by: Alex Bennée Message-Id: <20210612060828.695332-1-richard.henderson@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/mmap.c | 14 ++++++++++++++ linux-user/syscall.c | 12 ++++++++++++ 2 files changed, 26 insertions(+) diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 7e3b245036..0e103859fe 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -451,6 +451,20 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, goto fail; } + /* + * If we're mapping shared memory, ensure we generate code for parallel + * execution and flush old translations. This will work up to the level + * supported by the host -- anything that requires EXCP_ATOMIC will not + * be atomic with respect to an external process. + */ + if (flags & MAP_SHARED) { + CPUState *cpu = thread_cpu; + if (!(cpu->tcg_cflags & CF_PARALLEL)) { + cpu->tcg_cflags |= CF_PARALLEL; + tb_flush(cpu); + } + } + real_start = start & qemu_host_page_mask; host_offset = offset & qemu_host_page_mask; diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 974dd46c9a..54037db8d6 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -4603,6 +4603,7 @@ static inline abi_ulong target_shmlba(CPUArchState *cpu_env) static inline abi_ulong do_shmat(CPUArchState *cpu_env, int shmid, abi_ulong shmaddr, int shmflg) { + CPUState *cpu = env_cpu(cpu_env); abi_long raddr; void *host_raddr; struct shmid_ds shm_info; @@ -4633,6 +4634,17 @@ static inline abi_ulong do_shmat(CPUArchState *cpu_env, mmap_lock(); + /* + * We're mapping shared memory, so ensure we generate code for parallel + * execution and flush old translations. This will work up to the level + * supported by the host -- anything that requires EXCP_ATOMIC will not + * be atomic with respect to an external process. + */ + if (!(cpu->tcg_cflags & CF_PARALLEL)) { + cpu->tcg_cflags |= CF_PARALLEL; + tb_flush(cpu); + } + if (shmaddr) host_raddr = shmat(shmid, (void *)g2h_untagged(shmaddr), shmflg); else { From 144bff0304b8f93cf0eb9ed432434644302dc6d5 Mon Sep 17 00:00:00 2001 From: Michael Forney Date: Wed, 26 May 2021 12:02:03 -0700 Subject: [PATCH 2/9] linux-user: Disable static assert involving __SIGRTMAX if it is missing This check is to ensure that the loop in signal_table_init() from SIGRTMIN to SIGRTMAX falls within the bounds of host_to_target_signal_table (_NSIG). However, it is not critical, since _NSIG is already defined to be the one larger than the largest signal supported by the system (as specified in the upcoming POSIX revision[0]). musl libc does not define __SIGRTMAX, so disabling this check when it is missing fixes one of the last remaining errors when building qemu. [0] https://www.austingroupbugs.net/view.php?id=741 Signed-off-by: Michael Forney Reviewed-by: Laurent Vivier Message-Id: <20210526190203.4255-1-mforney@mforney.org> Signed-off-by: Laurent Vivier --- linux-user/signal.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/linux-user/signal.c b/linux-user/signal.c index 9016896dcd..0f19c59dee 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -38,7 +38,9 @@ static void host_signal_handler(int host_signum, siginfo_t *info, * Signal number 0 is reserved for use as kill(pid, 0), to test whether * a process exists without sending it a signal. */ +#ifdef __SIGRTMAX QEMU_BUILD_BUG_ON(__SIGRTMAX + 1 != _NSIG); +#endif static uint8_t host_to_target_signal_table[_NSIG] = { [SIGHUP] = TARGET_SIGHUP, [SIGINT] = TARGET_SIGINT, From 0e8876970401dee2055c1eb1c23f92f2e57d73ad Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Mon, 14 Jun 2021 15:42:45 +0100 Subject: [PATCH 3/9] linux-user/trace-events: fix minor typo in format string MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Alex Bennée Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Laurent Vivier Message-Id: <20210614144245.17660-1-alex.bennee@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/trace-events | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/linux-user/trace-events b/linux-user/trace-events index 1ec0d11ee3..e7d2f54e94 100644 --- a/linux-user/trace-events +++ b/linux-user/trace-events @@ -11,7 +11,7 @@ user_do_rt_sigreturn(void *env, uint64_t frame_addr) "env=%p frame_addr=0x%"PRIx user_do_sigreturn(void *env, uint64_t frame_addr) "env=%p frame_addr=0x%"PRIx64 user_force_sig(void *env, int target_sig, int host_sig) "env=%p signal %d (host %d)" user_handle_signal(void *env, int target_sig) "env=%p signal %d" -user_host_signal(void *env, int host_sig, int target_sig) "env=%p signal %d (target %d(" +user_host_signal(void *env, int host_sig, int target_sig) "env=%p signal %d (target %d)" user_queue_signal(void *env, int target_sig) "env=%p signal %d" user_s390x_restore_sigregs(void *env, uint64_t sc_psw_addr, uint64_t env_psw_addr) "env=%p frame psw.addr 0x%"PRIx64 " current psw.addr 0x%"PRIx64 From e10fbe8f34843891b18f68f76320b43606f4df69 Mon Sep 17 00:00:00 2001 From: YAMAMOTO Takashi Date: Mon, 31 May 2021 14:50:12 +0900 Subject: [PATCH 4/9] linux-user: Implement pivot_root Used by runc. Signed-off-by: YAMAMOTO Takashi Reviewed-by: Laurent Vivier Message-Id: <20210531055019.10149-6-yamamoto@midokura.com> Signed-off-by: Laurent Vivier --- linux-user/syscall.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 54037db8d6..723cb02d2a 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8257,6 +8257,10 @@ static int host_to_target_cpu_mask(const unsigned long *host_mask, return 0; } +#if defined(TARGET_NR_pivot_root) && defined(__NR_pivot_root) +_syscall2(int, pivot_root, const char *, new_root, const char *, put_old) +#endif + /* This is an internal helper for do_syscall so that it is easier * to have a single return point, so that actions, such as logging * of syscall results, can be performed. @@ -13220,6 +13224,23 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, return ret; #endif +#if defined(TARGET_NR_pivot_root) + case TARGET_NR_pivot_root: + { + void *p2; + p = lock_user_string(arg1); /* new_root */ + p2 = lock_user_string(arg2); /* put_old */ + if (!p || !p2) { + ret = -TARGET_EFAULT; + } else { + ret = get_errno(pivot_root(p, p2)); + } + unlock_user(p2, arg2, 0); + unlock_user(p, arg1, 0); + } + return ret; +#endif + default: qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num); return -TARGET_ENOSYS; From ee3500d33a7431fbcc357a35ce1a46fcf13128cc Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Tue, 1 Jun 2021 16:55:59 +0200 Subject: [PATCH 5/9] linux-user: Let sigaction query SIGKILL/SIGSTOP The kernel allows doing this, so let's allow this in qemu as well. Valgrind relies on this. Signed-off-by: Ilya Leoshkevich Reviewed-by: Laurent Vivier Message-Id: <20210601145600.3131040-2-iii@linux.ibm.com> Signed-off-by: Laurent Vivier --- linux-user/signal.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/linux-user/signal.c b/linux-user/signal.c index 0f19c59dee..a8faea6f09 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -853,7 +853,11 @@ int do_sigaction(int sig, const struct target_sigaction *act, trace_signal_do_sigaction_guest(sig, TARGET_NSIG); - if (sig < 1 || sig > TARGET_NSIG || sig == TARGET_SIGKILL || sig == TARGET_SIGSTOP) { + if (sig < 1 || sig > TARGET_NSIG) { + return -TARGET_EINVAL; + } + + if (act && (sig == TARGET_SIGKILL || sig == TARGET_SIGSTOP)) { return -TARGET_EINVAL; } From 1df0f5c1141958368d7473c7bfe8beac7bf86385 Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Tue, 1 Jun 2021 16:56:00 +0200 Subject: [PATCH 6/9] tests/tcg/linux-test: Check that sigaction can query SIGKILL/SIGSTOP Verify that querying is allowed, but making changes isn't. Signed-off-by: Ilya Leoshkevich Reviewed-by: Laurent Vivier Message-Id: <20210601145600.3131040-3-iii@linux.ibm.com> Signed-off-by: Laurent Vivier --- tests/tcg/multiarch/linux-test.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/tests/tcg/multiarch/linux-test.c b/tests/tcg/multiarch/linux-test.c index 96bbad5823..c8c6aeddeb 100644 --- a/tests/tcg/multiarch/linux-test.c +++ b/tests/tcg/multiarch/linux-test.c @@ -496,6 +496,15 @@ static void test_signal(void) sigemptyset(&act.sa_mask); act.sa_flags = 0; chk_error(sigaction(SIGSEGV, &act, NULL)); + + if (sigaction(SIGKILL, &act, NULL) == 0) { + error("sigaction(SIGKILL, &act, NULL) must not succeed"); + } + if (sigaction(SIGSTOP, &act, NULL) == 0) { + error("sigaction(SIGSTOP, &act, NULL) must not succeed"); + } + chk_error(sigaction(SIGKILL, NULL, &act)); + chk_error(sigaction(SIGSTOP, NULL, &act)); } #define SHM_SIZE 32768 From 8a589aeb271bb470884f960e76cd6a7c89c022c9 Mon Sep 17 00:00:00 2001 From: Khem Raj Date: Mon, 14 Jun 2021 12:17:29 -0700 Subject: [PATCH 7/9] linux-user: Check for ieee128 fpbits in PPC64 HWCAP2 feature list glibc 2.34 is now checking for this in hwcaps at runtime [1] and failing to run the binary if machine does not support 128bit IEEE fp Fixes Fatal glibc error: CPU lacks float128 support (POWER 9 or later required) [1] https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=d337345ce145e23c5f3a956f349d924fdf54ce2d;hp=eb24865637a271ab7dad13190330105eab0d478d Signed-off-by: Khem Raj Cc: Florian Weimer Reviewed-by: Laurent Vivier Message-Id: <20210614191729.2981488-1-raj.khem@gmail.com> Signed-off-by: Laurent Vivier --- linux-user/elfload.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 17ab06f612..e7dd18fd40 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -830,7 +830,7 @@ static uint32_t get_elf_hwcap2(void) PPC2_ISA207S), QEMU_PPC_FEATURE2_ARCH_2_07 | QEMU_PPC_FEATURE2_VEC_CRYPTO); GET_FEATURE2(PPC2_ISA300, QEMU_PPC_FEATURE2_ARCH_3_00 | - QEMU_PPC_FEATURE2_DARN); + QEMU_PPC_FEATURE2_DARN | QEMU_PPC_FEATURE2_HAS_IEEE128); #undef GET_FEATURE #undef GET_FEATURE2 From febf6fade63801ebca765797fa2ad9de8d9f2700 Mon Sep 17 00:00:00 2001 From: Michael Forney Date: Tue, 25 May 2021 20:55:31 -0700 Subject: [PATCH 8/9] linux-user: Fix incorrect use of feature-test-macros The _POSIX_C_SOURCE and _XOPEN_SOURCE macros are used by the application to indicate to libc which declarations it should expose. Since qemu does not define them anywhere, it does not make sense to check their value. Instead, since the intent is to determine whether the host struct stat supports the st_*tim fields, use the configure test result which does exactly that. Signed-off-by: Michael Forney Reviewed-by: Laurent Vivier Message-Id: <20210526035531.7871-1-mforney@mforney.org> Signed-off-by: Laurent Vivier --- linux-user/syscall.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 723cb02d2a..70ae8884ee 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -7482,7 +7482,7 @@ static inline abi_long host_to_target_stat64(void *cpu_env, __put_user(host_st->st_atime, &target_st->target_st_atime); __put_user(host_st->st_mtime, &target_st->target_st_mtime); __put_user(host_st->st_ctime, &target_st->target_st_ctime); -#if _POSIX_C_SOURCE >= 200809L || _XOPEN_SOURCE >= 700 +#ifdef HAVE_STRUCT_STAT_ST_ATIM __put_user(host_st->st_atim.tv_nsec, &target_st->target_st_atime_nsec); __put_user(host_st->st_mtim.tv_nsec, &target_st->target_st_mtime_nsec); __put_user(host_st->st_ctim.tv_nsec, &target_st->target_st_ctime_nsec); @@ -7517,7 +7517,7 @@ static inline abi_long host_to_target_stat64(void *cpu_env, __put_user(host_st->st_atime, &target_st->target_st_atime); __put_user(host_st->st_mtime, &target_st->target_st_mtime); __put_user(host_st->st_ctime, &target_st->target_st_ctime); -#if _POSIX_C_SOURCE >= 200809L || _XOPEN_SOURCE >= 700 +#ifdef HAVE_STRUCT_STAT_ST_ATIM __put_user(host_st->st_atim.tv_nsec, &target_st->target_st_atime_nsec); __put_user(host_st->st_mtim.tv_nsec, &target_st->target_st_mtime_nsec); __put_user(host_st->st_ctim.tv_nsec, &target_st->target_st_ctime_nsec); @@ -10072,8 +10072,7 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, __put_user(st.st_atime, &target_st->target_st_atime); __put_user(st.st_mtime, &target_st->target_st_mtime); __put_user(st.st_ctime, &target_st->target_st_ctime); -#if (_POSIX_C_SOURCE >= 200809L || _XOPEN_SOURCE >= 700) && \ - defined(TARGET_STAT_HAVE_NSEC) +#if defined(HAVE_STRUCT_STAT_ST_ATIM) && defined(TARGET_STAT_HAVE_NSEC) __put_user(st.st_atim.tv_nsec, &target_st->target_st_atime_nsec); __put_user(st.st_mtim.tv_nsec, From 96ff758c6e9cd5a01443ee15afbd0df4f00c37a8 Mon Sep 17 00:00:00 2001 From: Michael Forney Date: Tue, 25 May 2021 20:55:56 -0700 Subject: [PATCH 9/9] linux-user: Use public sigev_notify_thread_id member if available _sigev_un._tid is an internal glibc field and is not available on musl libc. The sigevent(7) man page and Linux UAPI headers both use sigev_notify_thread_id as a public way to access this field. musl libc supports this field since 1.2.2[0], and glibc plans to add support as well[1][2]. If sigev_notify_thread_id is not available, fall back to _sigev_un._tid as before. [0] http://git.musl-libc.org/cgit/musl/commit/?id=7c71792e87691451f2a6b76348e83ad1889f1dcb [1] https://www.openwall.com/lists/musl/2019/08/01/5 [2] https://sourceware.org/bugzilla/show_bug.cgi?id=27417 Signed-off-by: Michael Forney Reviewed-by: Laurent Vivier Message-Id: <20210526035556.7931-1-mforney@mforney.org> Signed-off-by: Laurent Vivier --- configure | 16 ++++++++++++++++ linux-user/syscall.c | 6 +++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/configure b/configure index 8dcb9965b2..942c531cce 100755 --- a/configure +++ b/configure @@ -4440,6 +4440,19 @@ if compile_prog "" "" ; then st_atim=yes fi +########################################## +# check if we have sigev_notify_thread_id + +sigev_notify_thread_id=no +cat > $TMPC << EOF +#include +#include +int main(void) { return offsetof(struct sigevent, sigev_notify_thread_id); } +EOF +if compile_prog "" "" ; then + sigev_notify_thread_id=yes +fi + ########################################## # check if trace backend exists @@ -5692,6 +5705,9 @@ fi if test "$st_atim" = "yes" ; then echo "HAVE_STRUCT_STAT_ST_ATIM=y" >> $config_host_mak fi +if test "$sigev_notify_thread_id" = "yes" ; then + echo "HAVE_SIGEV_NOTIFY_THREAD_ID=y" >> $config_host_mak +fi if test "$byteswap_h" = "yes" ; then echo "CONFIG_BYTESWAP_H=y" >> $config_host_mak fi diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 70ae8884ee..64bbf331b2 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -7405,6 +7405,10 @@ static inline abi_long host_to_target_timex64(abi_long target_addr, } #endif +#ifndef HAVE_SIGEV_NOTIFY_THREAD_ID +#define sigev_notify_thread_id _sigev_un._tid +#endif + static inline abi_long target_to_host_sigevent(struct sigevent *host_sevp, abi_ulong target_addr) { @@ -7425,7 +7429,7 @@ static inline abi_long target_to_host_sigevent(struct sigevent *host_sevp, host_sevp->sigev_signo = target_to_host_signal(tswap32(target_sevp->sigev_signo)); host_sevp->sigev_notify = tswap32(target_sevp->sigev_notify); - host_sevp->_sigev_un._tid = tswap32(target_sevp->_sigev_un._tid); + host_sevp->sigev_notify_thread_id = tswap32(target_sevp->_sigev_un._tid); unlock_user_struct(target_sevp, target_addr, 1); return 0;