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7cbeabac0f
This patch removes the vsyscall usage for x86_64 port. As indicated by kernel code comments [1], vsyscalls are a legacy ABI and its concept is problematic: - It interferes with ASLR. - It's awkward to write code that lives in kernel addresses but is callable by userspace at fixed addresses. - The whole concept is impossible for 32-bit compat userspace. - UML cannot easily virtualize a vsyscall. The VDSO is a better approach for such functionality. Tested on i686, x86_64, and x32. * sysdeps/unix/sysv/linux/i386/gettimeofday.c (__gettimeofday_syscall): Remove vsyscall fallback. * sysdeps/unix/sysv/linux/i386/time.c (__time_syscall): Likewise. * sysdeps/unix/sysv/linux/x86/gettimeofday.c (__gettimeofday_syscall): Add syscall fallback function. (gettimeofday_ifunc): Use __gettimeofday_syscall as fallback mechanism if vDSO is not present. * sysdeps/unix/sysv/linux/x86/time.c (__time_syscall): Add syscall fallback function. (time_ifunc): Use __time_syscall as fallback mechanism if vDSO is not present. * sysdeps/unix/sysv/linux/x86_64/gettimeofday.c: Remove file. * sysdeps/unix/sysv/linux/x86_64/time.c: Likewise. [1] arch/x86/kernel/vsyscall_64.c |
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| .. | ||
| bits | ||
| sys | ||
| elision-conf.c | ||
| elision-conf.h | ||
| elision-lock.c | ||
| elision-timed.c | ||
| elision-trylock.c | ||
| elision-unlock.c | ||
| force-elision.h | ||
| gettimeofday.c | ||
| hle.h | ||
| init-arch.c | ||
| init-arch.h | ||
| libc-vdso.h | ||
| Makefile | ||
| pthread_mutex_cond_lock.c | ||
| pthread_mutex_lock.c | ||
| pthread_mutex_timedlock.c | ||
| pthread_mutex_trylock.c | ||
| time.c | ||