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* x86/ia32/asm: Remove unused argument in macroRamkumar Ramachandra2013-07-231-1/+1
| | | | | | | | | | | | Commit 3fe26fa ("x86: get rid of pt_regs argument in sigreturn variants", from 2012-11-12) changed the body of PTREGSCALL to drop arg, and updated the callsites; unfortunately, it forgot to update the macro argument list, leaving an unused argument. Fix this. Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Link: http://lkml.kernel.org/r/1373479468-7175-1-git-send-email-artagnon@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-02-241-7/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull signal handling cleanups from Al Viro: "This is the first pile; another one will come a bit later and will contain SYSCALL_DEFINE-related patches. - a bunch of signal-related syscalls (both native and compat) unified. - a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE (fixing several potential problems with missing argument validation, while we are at it) - a lot of now-pointless wrappers killed - a couple of architectures (cris and hexagon) forgot to save altstack settings into sigframe, even though they used the (uninitialized) values in sigreturn; fixed. - microblaze fixes for delivery of multiple signals arriving at once - saner set of helpers for signal delivery introduced, several architectures switched to using those." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits) x86: convert to ksignal sparc: convert to ksignal arm: switch to struct ksignal * passing alpha: pass k_sigaction and siginfo_t using ksignal pointer burying unused conditionals make do_sigaltstack() static arm64: switch to generic old sigaction() (compat-only) arm64: switch to generic compat rt_sigaction() arm64: switch compat to generic old sigsuspend arm64: switch to generic compat rt_sigqueueinfo() arm64: switch to generic compat rt_sigpending() arm64: switch to generic compat rt_sigprocmask() arm64: switch to generic sigaltstack sparc: switch to generic old sigsuspend sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE sparc: kill sign-extending wrappers for native syscalls kill sparc32_open() sparc: switch to use of generic old sigaction sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE mips: switch to generic sys_fork() and sys_clone() ...
| * x86: get rid of pt_regs argument in sigreturn variantsAl Viro2013-02-041-6/+5
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * x86: get rid of pt_regs argument of iopl(2)Al Viro2013-02-041-1/+0
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | x86-64: Replace left over sti/cli in ia32 audit exit codeJan Beulich2013-01-311-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | For some reason they didn't get replaced so far by their paravirt equivalents, resulting in code to be run with interrupts disabled that doesn't expect so (causing, in the observed case, a BUG_ON() to trigger) when syscall auditing is enabled. David (Cc-ed) came up with an identical fix, so likely this can be taken to count as an ack from him. Reported-by: Peter Moody <pmoody@google.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Link: http://lkml.kernel.org/r/5108E01902000078000BA9C5@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Tested-by: Peter Moody <pmoody@google.com>
* generic compat_sys_sigaltstack()Al Viro2012-12-201-1/+0
| | | | | | Again, conditional on CONFIG_GENERIC_SIGALTSTACK Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86, um: switch to generic fork/vfork/cloneAl Viro2012-11-291-1/+6
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-10-101-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull generic execve() changes from Al Viro: "This introduces the generic kernel_thread() and kernel_execve() functions, and switches x86, arm, alpha, um and s390 over to them." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits) s390: convert to generic kernel_execve() s390: switch to generic kernel_thread() s390: fold kernel_thread_helper() into ret_from_fork() s390: fold execve_tail() into start_thread(), convert to generic sys_execve() um: switch to generic kernel_thread() x86, um/x86: switch to generic sys_execve and kernel_execve x86: split ret_from_fork alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve() alpha: switch to generic kernel_thread() alpha: switch to generic sys_execve() arm: get rid of execve wrapper, switch to generic execve() implementation arm: optimized current_pt_regs() arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve() arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk] generic sys_execve() generic kernel_execve() new helper: current_pt_regs() preparation for generic kernel_thread() um: kill thread->forking um: let signal_delivered() do SIGTRAP on singlestepping into handler ...
| * x86, um/x86: switch to generic sys_execve and kernel_execveAl Viro2012-10-011-1/+1
| | | | | | | | | | | | | | | | | | 32bit wrapper is lost on that; 64bit one is *not*, since we need to arrange for full pt_regs on stack when we call sys_execve() and we need to load callee-saved ones from there afterwards. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | x86, smap: Add STAC and CLAC instructions to control user space accessH. Peter Anvin2012-09-211-0/+6
|/ | | | | | | | | | | | | | | When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
* x86, extable: Remove open-coded exception table entries in ↵H. Peter Anvin2012-04-211-3/+1
| | | | | | | | | | | | | | arch/x86/ia32/ia32entry.S Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. This one was missed from the previous patch to this file. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
* x86, extable: Remove open-coded exception table entries in ↵H. Peter Anvin2012-04-201-3/+2
| | | | | | | | | | | | arch/x86/ia32/ia32entry.S Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
* Merge branch 'for-linus' of ↵Linus Torvalds2012-01-181-6/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits) audit: no leading space in audit_log_d_path prefix audit: treat s_id as an untrusted string audit: fix signedness bug in audit_log_execve_info() audit: comparison on interprocess fields audit: implement all object interfield comparisons audit: allow interfield comparison between gid and ogid audit: complex interfield comparison helper audit: allow interfield comparison in audit rules Kernel: Audit Support For The ARM Platform audit: do not call audit_getname on error audit: only allow tasks to set their loginuid if it is -1 audit: remove task argument to audit_set_loginuid audit: allow audit matching on inode gid audit: allow matching on obj_uid audit: remove audit_finish_fork as it can't be called audit: reject entry,always rules audit: inline audit_free to simplify the look of generic code audit: drop audit_set_macxattr as it doesn't do anything audit: inline checks for not needing to collect aux records audit: drop some potentially inadvisable likely notations ... Use evil merge to fix up grammar mistakes in Kconfig file. Bad speling and horrible grammar (and copious swearing) is to be expected, but let's keep it to commit messages and comments, rather than expose it to users in config help texts or printouts.
| * audit: inline audit_syscall_entry to reduce burden on archsEric Paris2012-01-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Every arch calls: if (unlikely(current->audit_context)) audit_syscall_entry() which requires knowledge about audit (the existance of audit_context) in the arch code. Just do it all in static inline in audit.h so that arch's can remain blissfully ignorant. Signed-off-by: Eric Paris <eparis@redhat.com>
| * audit: ia32entry.S sign extend error codes when calling 64 bit codeEric Paris2012-01-171-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the ia32entry syscall exit audit fastpath we have assembly code which calls __audit_syscall_exit directly. This code was, however, zeroes the upper 32 bits of the return code. It then proceeded to call code which expects longs to be 64bits long. In order to handle code which expects longs to be 64bit we sign extend the return code if that code is an error. Thus the __audit_syscall_exit function can correctly handle using the values in snprintf("%ld"). This fixes the regression introduced in 5cbf1565f29eb57a86a. Old record: type=SYSCALL msg=audit(1306197182.256:281): arch=40000003 syscall=192 success=no exit=4294967283 New record: type=SYSCALL msg=audit(1306197182.256:281): arch=40000003 syscall=192 success=no exit=-13 Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com>
| * Audit: push audit success and retcode into arch ptrace.hEric Paris2012-01-171-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The audit system previously expected arches calling to audit_syscall_exit to supply as arguments if the syscall was a success and what the return code was. Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things by converting from negative retcodes to an audit internal magic value stating success or failure. This helper was wrong and could indicate that a valid pointer returned to userspace was a failed syscall. The fix is to fix the layering foolishness. We now pass audit_syscall_exit a struct pt_reg and it in turns calls back into arch code to collect the return value and to determine if the syscall was a success or failure. We also define a generic is_syscall_success() macro which determines success/failure based on if the value is < -MAX_ERRNO. This works for arches like x86 which do not use a separate mechanism to indicate syscall failure. We make both the is_syscall_success() and regs_return_value() static inlines instead of macros. The reason is because the audit function must take a void* for the regs. (uml calls theirs struct uml_pt_regs instead of just struct pt_regs so audit_syscall_exit can't take a struct pt_regs). Since the audit function takes a void* we need to use static inlines to cast it back to the arch correct structure to dereference it. The other major change is that on some arches, like ia64, MIPS and ppc, we change regs_return_value() to give us the negative value on syscall failure. THE only other user of this macro, kretprobe_example.c, won't notice and it makes the value signed consistently for the audit functions across all archs. In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old audit code as the return value. But the ptrace_64.h code defined the macro regs_return_value() as regs[3]. I have no idea which one is correct, but this patch now uses the regs_return_value() function, so it now uses regs[3]. For powerpc we previously used regs->result but now use the regs_return_value() function which uses regs->gprs[3]. regs->gprs[3] is always positive so the regs_return_value(), much like ia64 makes it negative before calling the audit code when appropriate. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion] Acked-by: Tony Luck <tony.luck@intel.com> [for ia64] Acked-by: Richard Weinberger <richard@nod.at> [for uml] Acked-by: David S. Miller <davem@davemloft.net> [for sparc] Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips] Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
* | Merge branch 'x86-syscall-for-linus' of ↵Linus Torvalds2012-01-171-359/+0
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move <asm/asm-offsets.h> from trace_syscalls.c to asm/syscall.h x86, um: Fix typo in 32-bit system call modifications um: Use $(srctree) not $(KBUILD_SRC) x86, um: Mark system call tables readonly x86, um: Use the same style generated syscall tables as native um: Generate headers before generating user-offsets.s um: Run host archheaders, allow use of host generated headers kbuild, headers.sh: Don't make archheaders explicitly x86, syscall: Allow syscall offset to be symbolic x86, syscall: Re-fix typo in comment x86: Simplify syscallhdr.sh x86: Generate system call tables and unistd_*.h from tables checksyscalls: Use arch/x86/syscalls/syscall_32.tbl as source x86: Machine-readable syscall tables and scripts to process them trace: Include <asm/asm-offsets.h> in trace_syscalls.c x86-64, ia32: Move compat_ni_syscall into C and its own file x86-64, syscall: Adjust comment spacing and remove typo kbuild: Add support for an "archheaders" target kbuild: Add support for installing generated asm headers
| * x86: Generate system call tables and unistd_*.h from tablesH. Peter Anvin2011-11-171-356/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Generate system call tables and unistd_*.h automatically from the tables in arch/x86/syscalls. All other information, like NR_syscalls, is auto-generated, some of which is in asm-offsets_*.c. This allows us to keep all the system call information in one place, and allows for kernel space and user space to see different information; this is currently used for the ia32 system call numbers when building the 64-bit kernel, but will be used by the x32 ABI in the near future. This also removes some gratuitious differences between i386, x86-64 and ia32; in particular, now all system call tables are generated with the same mechanism. Cc: H. J. Lu <hjl.tools@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * x86-64, ia32: Move compat_ni_syscall into C and its own fileH. Peter Anvin2011-11-171-3/+0
| | | | | | | | | | | | | | | | Move compat_ni_syscall out of ia32entry.S and into its own .c file. Although this is a trivial function, it is not performance-critical, and this will simplify further cleanups. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86-64: Cleanup some assembly entry pointsJan Beulich2011-12-051-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | system_call_after_swapgs doesn't really benefit from forcing alignment from it - quite the opposite, native code needlessly so far got a big NOP instruction inserted in front of it. Xen being the only user of the separate entry point can well live with the branch going to three bytes into a cache line. The compatibility mode ptregs entry points for one can make use of the GLOBAL() macro, and should be suitably aligned. Their shared continuation point (ia32_ptregs_common) otoh doesn't need to be global at all, but should continue to be properly aligned. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/4ED4CEEA020000780006407D@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86-64: Slightly shorten line system call entry and exit pathsJan Beulich2011-12-051-21/+15
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GET_THREAD_INFO() involves a memory read immediately followed by an "sub" on the value read, in turn (in several cases) immediately followed by a use of the calculated value as the base address of a memory access. This combination of instructions has a non-negligible potential for stalls. In the system call entry point code, however, the (fixed) offset of the stack pointer from the end of the stack is generally known, and hence we can instead avoid the memory load and subtract, and instead do the memory reference using %rsp as the base register. To do so in a legible fashion, introduce a THREAD_INFO() macro which, provided a register (generally %rsp) and the known offset from the end of the stack, produces a suitable memory access operand. The patch attempts to only touch the fast paths (no auditing and alike), but manages to do so only in the 64-bit entry point case; the compatibility mode entry points have so many interdependencies between their various branch targets that it was necessary to also adjust the slow paths to eliminate the risk of having missed some register dependency during code analysis. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/4ED4CD690200007800064075@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Cross Memory AttachChristopher Yeoh2011-11-011-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The basic idea behind cross memory attach is to allow MPI programs doing intra-node communication to do a single copy of the message rather than a double copy of the message via shared memory. The following patch attempts to achieve this by allowing a destination process, given an address and size from a source process, to copy memory directly from the source process into its own address space via a system call. There is also a symmetrical ability to copy from the current process's address space into a destination process's address space. - Use of /proc/pid/mem has been considered, but there are issues with using it: - Does not allow for specifying iovecs for both src and dest, assuming preadv or pwritev was implemented either the area read from or written to would need to be contiguous. - Currently mem_read allows only processes who are currently ptrace'ing the target and are still able to ptrace the target to read from the target. This check could possibly be moved to the open call, but its not clear exactly what race this restriction is stopping (reason appears to have been lost) - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix domain socket is a bit ugly from a userspace point of view, especially when you may have hundreds if not (eventually) thousands of processes that all need to do this with each other - Doesn't allow for some future use of the interface we would like to consider adding in the future (see below) - Interestingly reading from /proc/pid/mem currently actually involves two copies! (But this could be fixed pretty easily) As mentioned previously use of vmsplice instead was considered, but has problems. Since you need the reader and writer working co-operatively if the pipe is not drained then you block. Which requires some wrapping to do non blocking on the send side or polling on the receive. In all to all communication it requires ordering otherwise you can deadlock. And in the example of many MPI tasks writing to one MPI task vmsplice serialises the copying. There are some cases of MPI collectives where even a single copy interface does not get us the performance gain we could. For example in an MPI_Reduce rather than copy the data from the source we would like to instead use it directly in a mathops (say the reduce is doing a sum) as this would save us doing a copy. We don't need to keep a copy of the data from the source. I haven't implemented this, but I think this interface could in the future do all this through the use of the flags - eg could specify the math operation and type and the kernel rather than just copying the data would apply the specified operation between the source and destination and store it in the destination. Although we don't have a "second user" of the interface (though I've had some nibbles from people who may be interested in using it for intra process messaging which is not MPI). This interface is something which hardware vendors are already doing for their custom drivers to implement fast local communication. And so in addition to this being useful for OpenMPI it would mean the driver maintainers don't have to fix things up when the mm changes. There was some discussion about how much faster a true zero copy would go. Here's a link back to the email with some testing I did on that: http://marc.info/?l=linux-mm&m=130105930902915&w=2 There is a basic man page for the proposed interface here: http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt This has been implemented for x86 and powerpc, other architecture should mainly (I think) just need to add syscall numbers for the process_vm_readv and process_vm_writev. There are 32 bit compatibility versions for 64-bit kernels. For arch maintainers there are some simple tests to be able to quickly verify that the syscalls are working correctly here: http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <linux-man@vger.kernel.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* All Arch: remove linkage for sys_nfsservctl system callNeilBrown2011-08-271-1/+1
| | | | | | | | | The nfsservctl system call is now gone, so we should remove all linkage for it. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86, asm: Flip RESTORE_ARGS arguments logicBorislav Petkov2011-06-031-2/+2
| | | | | | | | | | | ... thus getting rid of the "else" part of the conditional statement in the macro. No functionality change. Signed-off-by: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/1306873314-32523-4-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, asm: Flip SAVE_ARGS arguments logicBorislav Petkov2011-06-031-3/+3
| | | | | | | | | | This saves us the else part of the conditional statement in the macro. No functionality change. Signed-off-by: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/1306873314-32523-3-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* ns: Wire up the setns system callEric W. Biederman2011-05-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 32bit and 64bit on x86 are tested and working. The rest I have looked at closely and I can't find any problems. setns is an easy system call to wire up. It just takes two ints so I don't expect any weird architecture porting problems. While doing this I have noticed that we have some architectures that are very slow to get new system calls. cris seems to be the slowest where the last system calls wired up were preadv and pwritev. avr32 is weird in that recvmmsg was wired up but never declared in unistd.h. frv is behind with perf_event_open being the last syscall wired up. On h8300 the last system call wired up was epoll_wait. On m32r the last system call wired up was fallocate. mn10300 has recvmmsg as the last system call wired up. The rest seem to at least have syncfs wired up which was new in the 2.6.39. v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com> v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com> v4: Moved wiring up of the system call to another patch v5: ported to v2.6.39-rc6 v6: rebased onto parisc-next and net-next to avoid syscall conflicts. v7: ported to Linus's latest post 2.6.39 tree. >  arch/blackfin/include/asm/unistd.h     |    3 ++- >  arch/blackfin/mach-common/entry.S      |    1 + Acked-by: Mike Frysinger <vapier@gentoo.org> Oh - ia64 wiring looks good. Acked-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* net: Add sendmmsg socket system callAnton Blanchard2011-05-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a multiple message send syscall and is the send version of the existing recvmmsg syscall. This is heavily based on the patch by Arnaldo that added recvmmsg. I wrote a microbenchmark to test the performance gains of using this new syscall: http://ozlabs.org/~anton/junkcode/sendmmsg_test.c The test was run on a ppc64 box with a 10 Gbit network card. The benchmark can send both UDP and RAW ethernet packets. 64B UDP batch pkts/sec 1 804570 2 872800 (+ 8 %) 4 916556 (+14 %) 8 939712 (+17 %) 16 952688 (+18 %) 32 956448 (+19 %) 64 964800 (+20 %) 64B raw socket batch pkts/sec 1 1201449 2 1350028 (+12 %) 4 1461416 (+22 %) 8 1513080 (+26 %) 16 1541216 (+28 %) 32 1553440 (+29 %) 64 1557888 (+30 %) We see a 20% improvement in throughput on UDP send and 30% on raw socket send. [ Add sparc syscall entries. -DaveM ] Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* introduce sys_syncfs to sync a single file systemSage Weil2011-03-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is frequently useful to sync a single file system, instead of all mounted file systems via sync(2): - On machines with many mounts, it is not at all uncommon for some of them to hang (e.g. unresponsive NFS server). sync(2) will get stuck on those and may never get to the one you do care about (e.g., /). - Some applications write lots of data to the file system and then want to make sure it is flushed to disk. Calling fsync(2) on each file introduces unnecessary ordering constraints that result in a large amount of sub-optimal writeback/flush/commit behavior by the file system. There are currently two ways (that I know of) to sync a single super_block: - BLKFLSBUF ioctl on the block device: That also invalidates the bdev mapping, which isn't usually desirable, and doesn't work for non-block file systems. - 'mount -o remount,rw' will call sync_filesystem as an artifact of the current implemention. Relying on this little-known side effect for something like data safety sounds foolish. Both of these approaches require root privileges, which some applications do not have (nor should they need?) given that sync(2) is an unprivileged operation. This patch introduces a new system call syncfs(2) that takes an fd and syncs only the file system it references. Maybe someday we can $ sync /some/path and not get sync: ignoring all arguments The syscall is motivated by comments by Al and Christoph at the last LSF. syncfs(2) seems like an appropriate name given statfs(2). A similar ioctl was also proposed a while back, see http://marc.info/?l=linux-fsdevel&m=127970513829285&w=2 Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2011-03-161-18/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, binutils, xen: Fix another wrong size directive x86: Remove dead config option X86_CPU x86: Really print supported CPUs if PROCESSOR_SELECT=y x86: Fix a bogus unwind annotation in lib/semaphore_32.S um, x86-64: Fix UML build after adding CFI annotations to lib/rwsem_64.S x86: Remove unused bits from lib/thunk_*.S x86: Use {push,pop}_cfi in more places x86-64: Add CFI annotations to lib/rwsem_64.S x86, asm: Cleanup unnecssary macros in asm-offsets.c x86, system.h: Drop unused __SAVE/__RESTORE macros x86: Use bitmap library functions x86: Partly unify asm-offsets_{32,64}.c x86: Reduce back the alignment of the per-CPU data section
| * x86: Use {push,pop}_cfi in more placesJan Beulich2011-02-281-18/+9
| | | | | | | | | | | | | | | | | | Cleaning up and shortening code... Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Alexander van Heukelum <heukelum@fastmail.fm> LKML-Reference: <4D6BD35002000078000341DA@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2011-03-161-0/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (62 commits) posix-clocks: Check write permissions in posix syscalls hrtimer: Remove empty hrtimer_init_hres_timer() hrtimer: Update hrtimer->state documentation hrtimer: Update base[CLOCK_BOOTTIME].offset correctly timers: Export CLOCK_BOOTTIME via the posix timers interface timers: Add CLOCK_BOOTTIME hrtimer base time: Extend get_xtime_and_monotonic_offset() to also return sleep time: Introduce get_monotonic_boottime and ktime_get_boottime hrtimers: extend hrtimer base code to handle more then 2 clockids ntp: Remove redundant and incorrect parameter check mn10300: Switch do_timer() to xtimer_update() posix clocks: Introduce dynamic clocks posix-timers: Cleanup namespace posix-timers: Add support for fd based clocks x86: Add clock_adjtime for x86 posix-timers: Introduce a syscall for clock tuning. time: Splitout compat timex accessors ntp: Add ADJ_SETOFFSET mode bit time: Introduce timekeeping_inject_offset posix-timer: Update comment ... Fix up new system-call-related conflicts in arch/x86/ia32/ia32entry.S arch/x86/include/asm/unistd_32.h arch/x86/include/asm/unistd_64.h arch/x86/kernel/syscall_table_32.S (name_to_handle_at()/open_by_handle_at() vs clock_adjtime()), and some due to movement of get_jiffies_64() in: kernel/time.c
| * | x86: Add clock_adjtime for x86Richard Cochran2011-02-021-0/+1
| |/ | | | | | | | | | | | | | | | | This patch adds the clock_adjtime system call to the x86 architecture. Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Acked-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <20110201134419.968905083@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2011-03-161-0/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (184 commits) perf probe: Clean up probe_point_lazy_walker() return value tracing: Fix irqoff selftest expanding max buffer tracing: Align 4 byte ints together in struct tracer tracing: Export trace_set_clr_event() tracing: Explain about unstable clock on resume with ring buffer warning ftrace/graph: Trace function entry before updating index ftrace: Add .ref.text as one of the safe areas to trace tracing: Adjust conditional expression latency formatting. tracing: Fix event alignment: skb:kfree_skb tracing: Fix event alignment: mce:mce_record tracing: Fix event alignment: kvm:kvm_hv_hypercall tracing: Fix event alignment: module:module_request tracing: Fix event alignment: ftrace:context_switch and ftrace:wakeup tracing: Remove lock_depth from event entry perf header: Stop using 'self' perf session: Use evlist/evsel for managing perf.data attributes perf top: Don't let events to eat up whole header line perf top: Fix events overflow in top command ring-buffer: Remove unused #include <linux/trace_irq.h> tracing: Add an 'overwrite' trace_option. ...
| * | x86: Separate out entry text sectionJiri Olsa2011-03-081-0/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Put x86 entry code into a separate link section: .entry.text. Separating the entry text section seems to have performance benefits - caused by more efficient instruction cache usage. Running hackbench with perf stat --repeat showed that the change compresses the icache footprint. The icache load miss rate went down by about 15%: before patch: 19417627 L1-icache-load-misses ( +- 0.147% ) after patch: 16490788 L1-icache-load-misses ( +- 0.180% ) The motivation of the patch was to fix a particular kprobes bug that relates to the entry text section, the performance advantage was discovered accidentally. Whole perf output follows: - results for current tip tree: Performance counter stats for './hackbench/hackbench 10' (500 runs): 19417627 L1-icache-load-misses ( +- 0.147% ) 2676914223 instructions # 0.497 IPC ( +- 0.079% ) 5389516026 cycles ( +- 0.144% ) 0.206267711 seconds time elapsed ( +- 0.138% ) - results for current tip tree with the patch applied: Performance counter stats for './hackbench/hackbench 10' (500 runs): 16490788 L1-icache-load-misses ( +- 0.180% ) 2717734941 instructions # 0.502 IPC ( +- 0.079% ) 5414756975 cycles ( +- 0.148% ) 0.206747566 seconds time elapsed ( +- 0.137% ) Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: masami.hiramatsu.pt@hitachi.com Cc: ananth@in.ibm.com Cc: davem@davemloft.net Cc: 2nddept-manager@sdl.hitachi.co.jp LKML-Reference: <20110307181039.GB15197@jolsa.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* / x86: Add new syscalls for x86_64Aneesh Kumar K.V2011-03-151-0/+2
|/ | | | | | | This patch add new syscalls to x86_64 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86-64, compat: Retruncate rax after ia32 syscall entry tracingRoland McGrath2010-09-151-1/+7
| | | | | | | | | | | | | | In commit d4d6715, we reopened an old hole for a 64-bit ptracer touching a 32-bit tracee in system call entry. A %rax value set via ptrace at the entry tracing stop gets used whole as a 32-bit syscall number, while we only check the low 32 bits for validity. Fix it by truncating %rax back to 32 bits after syscall_trace_enter, in addition to testing the full 64 bits as has already been added. Reported-by: Ben Hawkes <hawkes@sota.gen.nz> Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86-64, compat: Test %rax for the syscall number, not %eaxH. Peter Anvin2010-09-151-7/+7
| | | | | | | | | | | | | | | | | | | | | On 64 bits, we always, by necessity, jump through the system call table via %rax. For 32-bit system calls, in theory the system call number is stored in %eax, and the code was testing %eax for a valid system call number. At one point we loaded the stored value back from the stack to enforce zero-extension, but that was removed in checkin d4d67150165df8bf1cc05e532f6efca96f907cab. An actual 32-bit process will not be able to introduce a non-zero-extended number, but it can happen via ptrace. Instead of re-introducing the zero-extension, test what we are actually going to use, i.e. %rax. This only adds a handful of REX prefixes to the code. Reported-by: Ben Hawkes <hawkes@sota.gen.nz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@kernel.org> Cc: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org>
* x86: fix up system call numbering nitLinus Torvalds2010-08-111-1/+1
| | | | | | | | | As pointed out by Jiri Slaby: when I resolved the the 32-bit x85 system call entry tables for prlimit (due to the conflict with fanotify), I forgot to add the numbering in comments that we do for every fifth entry. Reported-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linuxLinus Torvalds2010-08-101-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linux: unistd: add __NR_prlimit64 syscall numbers rlimits: implement prlimit64 syscall rlimits: switch more rlimit syscalls to do_prlimit rlimits: redo do_setrlimit to more generic do_prlimit rlimits: add rlimit64 structure rlimits: do security check under task_lock rlimits: allow setrlimit to non-current tasks rlimits: split sys_setrlimit rlimits: selinux, do rlimits changes under task_lock rlimits: make sure ->rlim_max never grows in sys_setrlimit rlimits: add task_struct to update_rlimit_cpu rlimits: security, add task_struct to setrlimit Fix up various system call number conflicts. We not only added fanotify system calls in the meantime, but asm-generic/unistd.h added a wait4 along with a range of reserved per-architecture system calls.
| * unistd: add __NR_prlimit64 syscall numbersJiri Slaby2010-07-161-0/+1
| | | | | | | | | | | | | | | | | | | | Add __NR_prlimit64 syscall numbers to asm-generic. Add them also to asm-x86, both 32 and 64-bit. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com>
* | fanotify: sys_fanotify_mark declartionEric Paris2010-07-281-0/+1
| | | | | | | | | | | | | | | | | | This patch simply declares the new sys_fanotify_mark syscall int fanotify_mark(int fanotify_fd, unsigned int flags, u64_mask, int dfd const char *pathname) Signed-off-by: Eric Paris <eparis@redhat.com>
* | fanotify: fanotify_init syscall declarationEric Paris2010-07-281-0/+1
|/ | | | | | | | | | | | This patch defines a new syscall fanotify_init() of the form: int sys_fanotify_init(unsigned int flags, unsigned int event_f_flags, unsigned int priority) This syscall is used to create and fanotify group. This is very similar to the inotify_init() syscall. Signed-off-by: Eric Paris <eparis@redhat.com>
* x86: correctly wire up the newuname system callChristoph Hellwig2010-04-201-1/+1
| | | | | | | | | | | | | | | | Before commit e28cbf22933d0c0ccaf3c4c27a1a263b41f73859 ("improve sys_newuname() for compat architectures") 64-bit x86 had a private implementation of sys_uname which was just called sys_uname, which other architectures used for the old uname. Due to some merge issues with the uname refactoring patches we ended up calling the old uname version for both the old and new system call slots, which lead to the domainname filed never be set which caused failures with libnss_nis. Reported-and-tested-by: Andy Isaacson <adi@hexapodia.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add generic sys_olduname()Christoph Hellwig2010-03-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Add generic implementations of the old and really old uname system calls. Note that sh only implements sys_olduname but not sys_oldolduname, but I'm not going to bother with another ifdef for that special case. m32r implemented an old uname but never wired it up, so kill it, too. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: James Morris <jmorris@namei.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add generic sys_old_select()Christoph Hellwig2010-03-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a generic implementation of the old select() syscall, which expects its argument in a memory block and switch all architectures over to use it. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Reviewed-by: H. Peter Anvin <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: James Morris <jmorris@namei.org> Acked-by: Andreas Schwab <schwab@linux-m68k.org> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Greg Ungerer <gerg@uclinux.org> Acked-by: David Howells <dhowells@redhat.com> Cc: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Unify sys_mmap*Al Viro2009-12-111-1/+1
| | | | | | | New helper - sys_mmap_pgoff(); switch syscalls to using it. Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds2009-12-081-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1815 commits) mac80211: fix reorder buffer release iwmc3200wifi: Enable wimax core through module parameter iwmc3200wifi: Add wifi-wimax coexistence mode as a module parameter iwmc3200wifi: Coex table command does not expect a response iwmc3200wifi: Update wiwi priority table iwlwifi: driver version track kernel version iwlwifi: indicate uCode type when fail dump error/event log iwl3945: remove duplicated event logging code b43: fix two warnings ipw2100: fix rebooting hang with driver loaded cfg80211: indent regulatory messages with spaces iwmc3200wifi: fix NULL pointer dereference in pmkid update mac80211: Fix TX status reporting for injected data frames ath9k: enable 2GHz band only if the device supports it airo: Fix integer overflow warning rt2x00: Fix padding bug on L2PAD devices. WE: Fix set events not propagated b43legacy: avoid PPC fault during resume b43: avoid PPC fault during resume tcp: fix a timewait refcnt race ... Fix up conflicts due to sysctl cleanups (dead sysctl_check code and CTL_UNNUMBERED removed) in kernel/sysctl_check.c net/ipv4/sysctl_net_ipv4.c net/ipv6/addrconf.c net/sctp/sysctl.c
| * Merge branch 'master' of ↵David S. Miller2009-11-191-16/+25
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/sfc/sfe4001.c drivers/net/wireless/libertas/cmd.c drivers/staging/Kconfig drivers/staging/Makefile drivers/staging/rtl8187se/Kconfig drivers/staging/rtl8192e/Kconfig
| * | net: Introduce recvmmsg socket syscallArnaldo Carvalho de Melo2009-10-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Meaning receive multiple messages, reducing the number of syscalls and net stack entry/exit operations. Next patches will introduce mechanisms where protocols that want to optimize this operation will provide an unlocked_recvmsg operation. This takes into account comments made by: . Paul Moore: sock_recvmsg is called only for the first datagram, sock_recvmsg_nosec is used for the rest. . Caitlin Bestler: recvmmsg now has a struct timespec timeout, that works in the same fashion as the ppoll one. If the underlying protocol returns a datagram with MSG_OOB set, this will make recvmmsg return right away with as many datagrams (+ the OOB one) it has received so far. . Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen datagrams and then recvmsg returns an error, recvmmsg will return the successfully received datagrams, store the error and return it in the next call. This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg, where we will be able to acquire the lock only at batch start and end, not at every underlying recvmsg call. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | sysctl: x86 Use the compat_sys_sysctlEric W. Biederman2009-11-061-1/+1
| |/ |/| | | | | | | | | | | | | | | | | Now that we have a generic 32bit compatibility implementation there is no need for x86 to implement it's own. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>