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* x86/entry: Get rid of two-phase syscall entry workAndy Lutomirski2016-06-141-6/+0
| | | | | | | | | I added two-phase syscall entry work back when the entry slow path was very slow. Nowadays, the entry slow path is fast and two-phase entry work serves no purpose. Remove it. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org>
* x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masksAndy Lutomirski2015-08-051-1/+0
| | | | | | | | | | | | | | | | | | | They are no longer used. Good riddance! Deleting the TIF_ macros is really nice. It was never clear why there were so many variants. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eric Paris <eparis@parisplace.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/22c61682f446628573dde0f1d573ab821677e06da.1438378274.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/32: Really make user_mode() work correctly for VM86 modeJan Beulich2015-05-291-1/+1
| | | | | | | | | | | | | | | | | | | | While commit efa7045103 ("x86/asm/entry: Make user_mode() work correctly if regs came from VM86 mode") claims that "user_mode() is now identical to user_mode_vm()", this wasn't actually the case - no prior commit made it so. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5566EB0D020000780007E655@mail.emea.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Remove user_mode_ignore_vm86()Ingo Molnar2015-03-311-17/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | user_mode_ignore_vm86() can be used instead of user_mode(), in places where we have already done a v8086_mode() security check of ptregs. But doing this check in the wrong place would be a bug that could result in security problems, and also the naming still isn't very clear. Furthermore, it only affects 32-bit kernels, while most development happens on 64-bit kernels. If we replace them with user_mode() checks then the cost is only a very minor increase in various slowpaths: text data bss dec hex filename 10573391 703562 1753042 13029995 c6d26b vmlinux.o.before 10573423 703562 1753042 13030027 c6d28b vmlinux.o.after So lets get rid of this distinction once and for all. Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150329090233.GA1963@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Remove user_mode_vm()Andy Lutomirski2015-03-231-5/+0
| | | | | | | | | | | | | | It has no callers anymore. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a594afd6a0bddb1311bd7c92a15201c87fbb8681.1426728647.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Make user_mode() work correctly if regs came from VM86 modeAndy Lutomirski2015-03-231-10/+7
| | | | | | | | | | | | | | | | user_mode() is now identical to user_mode_vm(). Subsequent patches will change all callers of user_mode_vm() to user_mode() and then delete user_mode_vm(). Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/0dd03eacb5f0a2b5ba0240de25347a31b493c289.1426728647.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Add user_mode_ignore_vm86()Andy Lutomirski2015-03-231-0/+17
| | | | | | | | | | | | | | | | | | | | user_mode() is dangerous and user_mode_vm() has a confusing name. Add user_mode_ignore_vm86() (equivalent to current user_mode()). We'll change the small number of legitimate users of user_mode() to user_mode_ignore_vm86(). Inspired by grsec, although this works rather differently. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/202c56ca63823c338af8e2e54948dbe222da6343.1426728647.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Fix execve() and sigreturn() syscalls to always return via IRETBrian Gerst2015-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both the execve() and sigreturn() family of syscalls have the ability to change registers in ways that may not be compatabile with the syscall path they were called from. In particular, SYSRET and SYSEXIT can't handle non-default %cs and %ss, and some bits in eflags. These syscalls have stubs that are hardcoded to jump to the IRET path, and not return to the original syscall path. The following commit: 76f5df43cab5e76 ("Always allocate a complete "struct pt_regs" on the kernel stack") recently changed this for some 32-bit compat syscalls, but introduced a bug where execve from a 32-bit program to a 64-bit program would fail because it still returned via SYSRETL. This caused Wine to fail when built for both 32-bit and 64-bit. This patch sets TIF_NOTIFY_RESUME for execve() and sigreturn() so that the IRET path is always taken on exit to userspace. Signed-off-by: Brian Gerst <brgerst@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1426978461-32089-1-git-send-email-brgerst@gmail.com [ Improved the changelog and comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/64: Save user RSP in pt_regs->sp on SYSCALL64 fastpathDenys Vlasenko2015-03-101-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Prepare for the removal of 'usersp', by simplifying PER_CPU(old_rsp) usage: - use it only as temp storage - store the userspace stack pointer immediately in pt_regs->sp on syscall entry, instead of using it later, on syscall exit. - change C code to use pt_regs->sp only, instead of PER_CPU(old_rsp) and task->thread.usersp. FIXUP/RESTORE_TOP_OF_STACK are simplified as well. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1425926364-9526-4-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/64: Fix commentsDenys Vlasenko2015-03-041-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | - Misleading and slightly incorrect comments in "struct pt_regs" are fixed (four instances). - Fix incorrect comment atop EMPTY_FRAME macro. - Explain in more detail what we do with stack layout during hw interrupt. - Correct comments about "partial stack frame" which are no longer true. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1423778052-21038-3-git-send-email-dvlasenk@redhat.com Link: http://lkml.kernel.org/r/e1f4429c491fe6ceeddb879dea2786e0f8920f9c.1424989793.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86: Split syscall_trace_enter into two phasesAndy Lutomirski2014-09-081-0/+5
| | | | | | | | | | | | | | | | | | | | This splits syscall_trace_enter into syscall_trace_enter_phase1 and syscall_trace_enter_phase2. Only phase 2 has full pt_regs, and only phase 2 is permitted to modify any of pt_regs except for orig_ax. The intent is that phase 1 can be called from the syscall fast path. In this implementation, phase1 can handle any combination of TIF_NOHZ (RCU context tracking), TIF_SECCOMP, and TIF_SYSCALL_AUDIT, unless seccomp requests a ptrace event, in which case phase2 is forced. In principle, this could yield a big speedup for TIF_NOHZ as well as for TIF_SECCOMP if syscall exit work were similarly split up. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2df320a600020fda055fccf2b668145729dd0c04.1409954077.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* ptrace,x86: force IRET path after a ptrace_stop()Tejun Heo2014-07-041-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | The 'sysret' fastpath does not correctly restore even all regular registers, much less any segment registers or reflags values. That is very much part of why it's faster than 'iret'. Normally that isn't a problem, because the normal ptrace() interface catches the process using the signal handler infrastructure, which always returns with an iret. However, some paths can get caught using ptrace_event() instead of the signal path, and for those we need to make sure that we aren't going to return to user space using 'sysret'. Otherwise the modifications that may have been done to the register set by the tracer wouldn't necessarily take effect. Fix it by forcing IRET path by setting TIF_NOTIFY_RESUME from arch_ptrace_stop_needed() which is invoked from ptrace_stop(). Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Oleg Nesterov <oleg@redhat.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Delete non-required instances of include <linux/init.h>Paul Gortmaker2014-01-071-1/+0
| | | | | | | | | | | | | None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. [ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-12-211-0/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull signal handling cleanups from Al Viro: "sigaltstack infrastructure + conversion for x86, alpha and um, COMPAT_SYSCALL_DEFINE infrastructure. Note that there are several conflicts between "unify SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline; resolution is trivial - just remove definitions of SS_ONSTACK and SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and include/uapi/linux/signal.h contains the unified variant." Fixed up conflicts as per Al. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: alpha: switch to generic sigaltstack new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those generic compat_sys_sigaltstack() introduce generic sys_sigaltstack(), switch x86 and um to it new helper: compat_user_stack_pointer() new helper: restore_altstack() unify SS_ONSTACK/SS_DISABLE definitions new helper: current_user_stack_pointer() missing user_stack_pointer() instances Bury the conditionals from kernel_thread/kernel_execve series COMPAT_SYSCALL_DEFINE: infrastructure
| * new helper: compat_user_stack_pointer()Al Viro2012-12-201-0/+7
| | | | | | | | | | | | | | | | | | | | | | Compat counterpart of current_user_stack_pointer(); for most of the biarch architectures those two are identical, but e.g. arm64 and arm use different registers for stack pointer... Note that amd64 variants of current_user_stack_pointer/compat_user_stack_pointer do *not* rely on pt_regs having been through FIXUP_TOP_OF_STACK. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | UAPI: (Scripted) Disintegrate arch/x86/include/asmDavid Howells2012-12-141-74/+1
| | | | | | | | | | | | | | | | | | Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
* | Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2012-12-121-0/+9
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm changes from Ingo Molnar: "Two fixlets and a cleanup." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86_32: Return actual stack when requesting sp from regs x86: Don't clobber top of pt_regs in nested NMI x86/asm: Clean up copy_page_*() comments and code
| * x86_32: Return actual stack when requesting sp from regsSteven Rostedt2012-11-191-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As x86_32 traps do not save sp when taken in kernel mode, we need to accommodate the sp when requesting to get the register. This affects kprobes. Before: # echo 'p:ftrace sys_read+4 s=%sp' > /debug/tracing/kprobe_events # echo 1 > /debug/tracing/events/kprobes/enable # cat trace sshd-1345 [000] d... 489.117168: ftrace: (sys_read+0x4/0x70) s=b7e96768 sshd-1345 [000] d... 489.117191: ftrace: (sys_read+0x4/0x70) s=b7e96768 cat-1447 [000] d... 489.117392: ftrace: (sys_read+0x4/0x70) s=5a7 cat-1447 [001] d... 489.118023: ftrace: (sys_read+0x4/0x70) s=b77ad05f less-1448 [000] d... 489.118079: ftrace: (sys_read+0x4/0x70) s=b7762e06 less-1448 [000] d... 489.118117: ftrace: (sys_read+0x4/0x70) s=b7764970 After: sshd-1352 [000] d... 362.348016: ftrace: (sys_read+0x4/0x70) s=f3febfa8 sshd-1352 [000] d... 362.348048: ftrace: (sys_read+0x4/0x70) s=f3febfa8 bash-1355 [001] d... 362.348081: ftrace: (sys_read+0x4/0x70) s=f5075fa8 sshd-1352 [000] d... 362.348082: ftrace: (sys_read+0x4/0x70) s=f3febfa8 sshd-1352 [000] d... 362.690950: ftrace: (sys_read+0x4/0x70) s=f3febfa8 bash-1355 [001] d... 362.691033: ftrace: (sys_read+0x4/0x70) s=f5075fa8 Link: http://lkml.kernel.org/r/1342208654.30075.22.camel@gandalf.stny.rr.com Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | x86-32: Fix invalid stack address while in softirqRobert Richter2012-11-211-11/+4
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In 32 bit the stack address provided by kernel_stack_pointer() may point to an invalid range causing NULL pointer access or page faults while in NMI (see trace below). This happens if called in softirq context and if the stack is empty. The address at &regs->sp is then out of range. Fixing this by checking if regs and &regs->sp are in the same stack context. Otherwise return the previous stack pointer stored in struct thread_info. If that address is invalid too, return address of regs. BUG: unable to handle kernel NULL pointer dereference at 0000000a IP: [<c1004237>] print_context_stack+0x6e/0x8d *pde = 00000000 Oops: 0000 [#1] SMP Modules linked in: Pid: 4434, comm: perl Not tainted 3.6.0-rc3-oprofile-i386-standard-g4411a05 #4 Hewlett-Packard HP xw9400 Workstation/0A1Ch EIP: 0060:[<c1004237>] EFLAGS: 00010093 CPU: 0 EIP is at print_context_stack+0x6e/0x8d EAX: ffffe000 EBX: 0000000a ECX: f4435f94 EDX: 0000000a ESI: f4435f94 EDI: f4435f94 EBP: f5409ec0 ESP: f5409ea0 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 8005003b CR2: 0000000a CR3: 34ac9000 CR4: 000007d0 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 DR6: ffff0ff0 DR7: 00000400 Process perl (pid: 4434, ti=f5408000 task=f5637850 task.ti=f4434000) Stack: 000003e8 ffffe000 00001ffc f4e39b00 00000000 0000000a f4435f94 c155198c f5409ef0 c1003723 c155198c f5409f04 00000000 f5409edc 00000000 00000000 f5409ee8 f4435f94 f5409fc4 00000001 f5409f1c c12dce1c 00000000 c155198c Call Trace: [<c1003723>] dump_trace+0x7b/0xa1 [<c12dce1c>] x86_backtrace+0x40/0x88 [<c12db712>] ? oprofile_add_sample+0x56/0x84 [<c12db731>] oprofile_add_sample+0x75/0x84 [<c12ddb5b>] op_amd_check_ctrs+0x46/0x260 [<c12dd40d>] profile_exceptions_notify+0x23/0x4c [<c1395034>] nmi_handle+0x31/0x4a [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13950ed>] do_nmi+0xa0/0x2ff [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13949e5>] nmi_stack_correct+0x28/0x2d [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c1003603>] ? do_softirq+0x4b/0x7f <IRQ> [<c102a06f>] irq_exit+0x35/0x5b [<c1018f56>] smp_apic_timer_interrupt+0x6c/0x7a [<c1394746>] apic_timer_interrupt+0x2a/0x30 Code: 89 fe eb 08 31 c9 8b 45 0c ff 55 ec 83 c3 04 83 7d 10 00 74 0c 3b 5d 10 73 26 3b 5d e4 73 0c eb 1f 3b 5d f0 76 1a 3b 5d e8 73 15 <8b> 13 89 d0 89 55 e0 e8 ad 42 03 00 85 c0 8b 55 e0 75 a6 eb cc EIP: [<c1004237>] print_context_stack+0x6e/0x8d SS:ESP 0068:f5409ea0 CR2: 000000000000000a ---[ end trace 62afee3481b00012 ]--- Kernel panic - not syncing: Fatal exception in interrupt V2: * add comments to kernel_stack_pointer() * always return a valid stack address by falling back to the address of regs Reported-by: Yang Wei <wei.yang@windriver.com> Cc: <stable@vger.kernel.org> Signed-off-by: Robert Richter <robert.richter@amd.com> Link: http://lkml.kernel.org/r/20120912135059.GZ8285@erda.amd.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jun Zhang <jun.zhang@intel.com>
* x86: Move some signal-handling definitions to a common headerH. Peter Anvin2012-02-201-1/+0
| | | | | | | | | | | | | | | There are some definitions which are duplicated between kernel/signal.c and ia32/ia32_signal.c; move them to a common header file. Rather than adding stuff to existing header files which contain data structures, create a new header file; hence the slightly odd name ("all the good ones were taken.") Note: nothing relied on signal_fault() being defined in <asm/ptrace.h>. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86-64: Add user_64bit_mode paravirt opAndy Lutomirski2011-08-051-0/+19
| | | | | | | | | | | | | | | | | | | | | | Three places in the kernel assume that the only long mode CPL 3 selector is __USER_CS. This is not true on Xen -- Xen's sysretq changes cs to the magic value 0xe033. Two of the places are corner cases, but as of "x86-64: Improve vsyscall emulation CS and RIP handling" (c9712944b2a12373cb6ff8059afcfb7e826a6c54), vsyscalls will segfault if called with Xen's extra CS selector. This causes a panic when older init builds die. It seems impossible to make Xen use __USER_CS reliably without taking a performance hit on every system call, so this fixes the tests instead with a new paravirt op. It's a little ugly because ptrace.h can't include paravirt.h. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/f4fcb3947340d9e96ce1054a432f183f9da9db83.1312378163.git.luto@mit.edu Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86: convert to asm-generic ptrace.hMike Frysinger2011-05-271-13/+5
| | | | | | | | | | | | | | Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Sergei Shtylyov <sshtylyov@mvista.com> Cc: Dongdong Deng <dongdong.deng@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Fix common misspellingsLucas De Marchi2011-03-181-2/+2
| | | | | | | | | They were generated by 'codespell' and then manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: trivial@kernel.org LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, perf, bts, mm: Delete the never used BTS-ptrace codePeter Zijlstra2010-03-261-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | Support for the PMU's BTS features has been upstreamed in v2.6.32, but we still have the old and disabled ptrace-BTS, as Linus noticed it not so long ago. It's buggy: TIF_DEBUGCTLMSR is trampling all over that MSR without regard for other uses (perf) and doesn't provide the flexibility needed for perf either. Its users are ptrace-block-step and ptrace-bts, since ptrace-bts was never used and ptrace-block-step can be implemented using a much simpler approach. So axe all 3000 lines of it. That includes the *locked_memory*() APIs in mm/mlock.c as well. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Markus Metzger <markus.t.metzger@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20100325135413.938004390@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* ptrace: move user_enable_single_step & co prototypes to linux/ptrace.hChristoph Hellwig2010-03-131-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While in theory user_enable_single_step/user_disable_single_step/ user_enable_blockstep could also be provided as an inline or macro there's no good reason to do so, and having the prototype in one places keeps code size and confusion down. Roland said: The original thought there was that user_enable_single_step() et al might well be only an instruction or three on a sane machine (as if we have any of those!), and since there is only one call site inlining would be beneficial. But I agree that there is no strong reason to care about inlining it. As to the arch changes, there is only one thought I'd add to the record. It was always my thinking that for an arch where PTRACE_SINGLESTEP does text-modifying breakpoint insertion, user_enable_single_step() should not be provided. That is, arch_has_single_step()=>true means that there is an arch facility with "pure" semantics that does not have any unexpected side effects. Inserting a breakpoint might do very unexpected strange things in multi-threaded situations. Aside from that, it is a peculiar side effect that user_{enable,disable}_single_step() should cause COW de-sharing of text pages and so forth. For PTRACE_SINGLESTEP, all these peculiarities are the status quo ante for that arch, so having arch_ptrace() itself do those is one thing. But for building other things in the future, it is nicer to have a uniform "pure" semantics that arch-independent code can expect. OTOH, all such arch issues are really up to the arch maintainer. As of today, there is nothing but ptrace using user_enable_single_step() et al so it's a distinction without a practical difference. If/when there are other facilities that use user_enable_single_step() and might care, the affected arch's can revisit the question when someone cares about the quality of the arch support for said new facility. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86/ptrace: Remove unused regs_get_argument_nth APIMasami Hiramatsu2010-01-131-4/+0
| | | | | | | | | | | | | | | | | | | | | Because of dropping function argument syntax from kprobe-tracer, we don't need this API anymore. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Neuling <mikey@neuling.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linuxppc-dev@ozlabs.org LKML-Reference: <20100105224656.19431.92588.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* ptrace: x86: implement user_single_step_siginfo()Oleg Nesterov2009-12-161-0/+2
| | | | | | | | | | | | | | | | | | | Suggested by Roland. Implement user_single_step_siginfo() for x86. Extract this code from send_sigtrap(). Since x86 calls tracehook_report_syscall_exit(step => 0) the new helper is not used yet. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Cc: <linux-arch@vger.kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Fix comments of register/stack access functionsMasami Hiramatsu2009-12-021-4/+4
| | | | | | | | | | | | | | | | | Fix typos and some redundant comments of register/stack access functions in asm/ptrace.h. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Wenji Huang <wenji.huang@oracle.com> Cc: Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> LKML-Reference: <20091201000222.7669.7477.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu> Suggested-by: Wenji Huang <wenji.huang@oracle.com>
* x86: Add pt_regs register and stack access APIsMasami Hiramatsu2009-08-271-0/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add following APIs for accessing registers and stack entries from pt_regs. These APIs are required by kprobes-based event tracer on ftrace. Some other debugging tools might be able to use it too. - regs_query_register_offset(const char *name) Query the offset of "name" register. - regs_query_register_name(unsigned int offset) Query the name of register by its offset. - regs_get_register(struct pt_regs *regs, unsigned int offset) Get the value of a register by its offset. - regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) Check the address is in the kernel stack. - regs_get_kernel_stack_nth(struct pt_regs *reg, unsigned int nth) Get Nth entry of the kernel stack. (N >= 0) - regs_get_argument_nth(struct pt_regs *reg, unsigned int nth) Get Nth argument at function call. (N >= 0) Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: linux-arch@vger.kernel.org Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jason Baron <jbaron@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it> Cc: Roland McGrath <roland@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Vegard Nossum <vegard.nossum@gmail.com> LKML-Reference: <20090813203444.31965.26374.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* Merge branch 'tracing-for-linus' of ↵Linus Torvalds2009-06-111-5/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits) Revert "x86, bts: reenable ptrace branch trace support" tracing: do not translate event helper macros in print format ftrace/documentation: fix typo in function grapher name tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK tracing: add protection around module events unload tracing: add trace_seq_vprint interface tracing: fix the block trace points print size tracing/events: convert block trace points to TRACE_EVENT() ring-buffer: fix ret in rb_add_time_stamp ring-buffer: pass in lockdep class key for reader_lock tracing: add annotation to what type of stack trace is recorded tracing: fix multiple use of __print_flags and __print_symbolic tracing/events: fix output format of user stack tracing/events: fix output format of kernel stack tracing/trace_stack: fix the number of entries in the header ring-buffer: discard timestamps that are at the start of the buffer ring-buffer: try to discard unneeded timestamps ring-buffer: fix bug in ring_buffer_discard_commit ftrace: do not profile functions when disabled tracing: make trace pipe recognize latency format flag ...
| * x86, ptrace: add bts context unconditionallyMarkus Metzger2009-04-071-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the ptrace bts context field to task_struct unconditionally. Initialize the field directly in copy_process(). Remove all the unneeded functionality used to initialize that field. Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Cc: roland@redhat.com Cc: eranian@googlemail.com Cc: oleg@redhat.com Cc: juan.villacis@intel.com Cc: ak@linux.jf.intel.com LKML-Reference: <20090403144603.292754000@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86, 32-bit: fix kernel_trap_sp()Masami Hiramatsu2009-05-121-3/+4
|/ | | | | | | | | | | | | | | | | Use &regs->sp instead of regs for getting the top of stack in kernel mode. (on x86-64, regs->sp always points the top of stack) [ Impact: Oprofile decodes only stack for backtracing on i386 ] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> [ v2: rename the API to kernel_stack_pointer(), move variable inside ] Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: systemtap@sources.redhat.com Cc: Harvey Harrison <harvey.harrison@gmail.com> Cc: Jan Blunck <jblunck@suse.de> Cc: Christoph Hellwig <hch@infradead.org> LKML-Reference: <20090511210300.17332.67549.stgit@localhost.localdomain> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: make lazy %gs optional on x86_32Tejun Heo2009-02-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: pt_regs changed, lazy gs handling made optional, add slight overhead to SAVE_ALL, simplifies error_code path a bit On x86_32, %gs hasn't been used by kernel and handled lazily. pt_regs doesn't have place for it and gs is saved/loaded only when necessary. In preparation for stack protector support, this patch makes lazy %gs handling optional by doing the followings. * Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs. * Save and restore %gs along with other registers in entry_32.S unless LAZY_GS. Note that this unfortunately adds "pushl $0" on SAVE_ALL even when LAZY_GS. However, it adds no overhead to common exit path and simplifies entry path with error code. * Define different user_gs accessors depending on LAZY_GS and add lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS. The lazy_*_gs() ops are used to save, load and clear %gs lazily. * Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly. xen and lguest changes need to be verified. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, bts: add fork and exit handlingMarkus Metzger2008-12-201-0/+7
| | | | | | | | | | | | | | | | | | | | Impact: introduce new ptrace facility Add arch_ptrace_untrace() function that is called when the tracer detaches (either voluntarily or when the tracing task dies); ptrace_disable() is only called on a voluntary detach. Add ptrace_fork() and arch_ptrace_fork(). They are called when a traced task is forked. Clear DS and BTS related fields on fork. Release DS resources and reclaim memory in ptrace_untrace(). This releases resources already when the tracing task dies. We used to do that when the traced task dies. Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, bts: provide in-kernel branch-trace interfaceMarkus Metzger2008-12-121-36/+0
| | | | | | | | | Impact: cleanup Move the BTS bits from ptrace.c into ds.c. Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* remove __ARCH_WANT_COMPAT_SYS_PTRACEChristoph Hellwig2008-11-301-2/+0
| | | | | | | | | | | | | All architectures now use the generic compat_sys_ptrace, as should every new architecture that needs 32bit compat (if we'll ever get another). Remove the now superflous __ARCH_WANT_COMPAT_SYS_PTRACE define, and also kill a comment about __ARCH_SYS_PTRACE that was added after __ARCH_SYS_PTRACE was already gone. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Fix ASM_X86__ header guardsH. Peter Anvin2008-10-231-3/+3
| | | | | | | | | Change header guards named "ASM_X86__*" to "_ASM_X86_*" since: a. the double underscore is ugly and pointless. b. no leading underscore violates namespace constraints. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: ... and asm-x86 moveAl Viro2008-10-231-0/+280
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>