kernel.git/arch/x86/include/asm/elf.h, branch linux-3.10.y

x86/vdso: Plug race between mapping and ELF header setup

2017-06-20T12:04:44Z

commit 6fdc6dd90272ce7e75d744f71535cfbd8d77da81 upstream. The vsyscall32 sysctl can racy against a concurrent fork when it switches from disabled to enabled: arch_setup_additional_pages() if (vdso32_enabled) --> No mapping sysctl.vsysscall32() --> vdso32_enabled = true create_elf_tables() ARCH_DLINFO_IA32 if (vdso32_enabled) { --> Add VDSO entry with NULL pointer Make ARCH_DLINFO_IA32 check whether the VDSO mapping has been set up for the newly forked process or not. Signed-off-by: Thomas Gleixner Acked-by: Andy Lutomirski Cc: Peter Zijlstra Cc: Mathias Krause Link: http://lkml.kernel.org/r/20170410151723.602367196@linutronix.de Signed-off-by: Thomas Gleixner Signed-off-by: Willy Tarreau

x86: Reject x32 executables if x32 ABI not supported

2014-11-14T16:47:54Z

commit 0e6d3112a4e95d55cf6dca88f298d5f4b8f29bd1 upstream. It is currently possible to execve() an x32 executable on an x86_64 kernel that has only ia32 compat enabled. However all its syscalls will fail, even _exit(). This usually causes it to segfault. Change the ELF compat architecture check so that x32 executables are rejected if we don't support the x32 ABI. Signed-off-by: Ben Hutchings Link: http://lkml.kernel.org/r/1410120305.6822.9.camel@decadent.org.uk Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

mm: use vm_unmapped_area() on x86_64 architecture

2012-12-12T01:22:25Z

Update the x86_64 arch_get_unmapped_area[_topdown] functions to make use of vm_unmapped_area() instead of implementing a brute force search. Signed-off-by: Michel Lespinasse Reviewed-by: Rik van Riel Cc: Hugh Dickins Cc: Russell King Cc: Ralf Baechle Cc: Paul Mundt Cc: "David S. Miller" Cc: Chris Metcalf Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-03-30T01:12:23Z

Pull x32 support for x86-64 from Ingo Molnar: "This tree introduces the X32 binary format and execution mode for x86: 32-bit data space binaries using 64-bit instructions and 64-bit kernel syscalls. This allows applications whose working set fits into a 32 bits address space to make use of 64-bit instructions while using a 32-bit address space with shorter pointers, more compressed data structures, etc." Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c} * 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) x32: Fix alignment fail in struct compat_siginfo x32: Fix stupid ia32/x32 inversion in the siginfo format x32: Add ptrace for x32 x32: Switch to a 64-bit clock_t x32: Provide separate is_ia32_task() and is_x32_task() predicates x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls x86/x32: Fix the binutils auto-detect x32: Warn and disable rather than error if binutils too old x32: Only clear TIF_X32 flag once x32: Make sure TS_COMPAT is cleared for x32 tasks fs: Remove missed ->fds_bits from cessation use of fd_set structs internally fs: Fix close_on_exec pointer in alloc_fdtable x32: Drop non-__vdso weak symbols from the x32 VDSO x32: Fix coding style violations in the x32 VDSO code x32: Add x32 VDSO support x32: Allow x32 to be configured x32: If configured, add x32 system calls to system call tables x32: Handle process creation x32: Signal-related system calls x86: Add #ifdef CONFIG_COMPAT to ...

Disintegrate asm/system.h for X86

2012-03-28T17:11:12Z

Disintegrate asm/system.h for X86. Signed-off-by: David Howells Acked-by: H. Peter Anvin cc: x86@kernel.org

x32: Fix coding style violations in the x32 VDSO code

2012-02-21T22:32:19Z

Move the prototype for x32_setup_additional_pages() to a header file, and adjust the coding style to match standard. Signed-off-by: H. Peter Anvin Cc: H. J. Lu

x32: Handle process creation

2012-02-20T20:52:05Z

Allow an x32 process to be started. Originally-by: H. J. Lu Signed-off-by: H. Peter Anvin Cc: Peter Zijlstra

x86: Factor out TIF_IA32 from 32-bit address space

2012-02-20T20:48:46Z

Factor out IA32 (compatibility instruction set) from 32-bit address space in the thread_info flags; this is a precondition patch for x32 support. Originally-by: H. J. Lu Signed-off-by: H. Peter Anvin Link: http://lkml.kernel.org/n/tip-4pr1xnnksprt7t0h3w5fw4rv@git.kernel.org

x86, amd: Avoid cache aliasing penalties on AMD family 15h

2011-08-05T19:26:44Z

This patch provides performance tuning for the "Bulldozer" CPU. With its shared instruction cache there is a chance of generating an excessive number of cache cross-invalidates when running specific workloads on the cores of a compute module. This excessive amount of cross-invalidations can be observed if cache lines backed by shared physical memory alias in bits [14:12] of their virtual addresses, as those bits are used for the index generation. This patch addresses the issue by clearing all the bits in the [14:12] slice of the file mapping's virtual address at generation time, thus forcing those bits the same for all mappings of a single shared library across processes and, in doing so, avoids instruction cache aliases. It also adds the command line option "align_va_addr=(32|64|on|off)" with which virtual address alignment can be enabled for 32-bit or 64-bit x86 individually, or both, or be completely disabled. This change leaves virtual region address allocation on other families and/or vendors unaffected. Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1312550110-24160-2-git-send-email-bp@amd64.org Signed-off-by: H. Peter Anvin

x86: ELF_PLAT_INIT() shouldn't worry about TIF_IA32

2010-02-16T16:51:49Z

The 64-bit version of ELF_PLAT_INIT() clears TIF_IA32, but at this point it has already been cleared by SET_PERSONALITY == set_personality_64bit. Signed-off-by: Oleg Nesterov Signed-off-by: Linus Torvalds