1. 24 Aug, 2016 15 commits
    • Brian Gerst's avatar
      sched/x86/64, kgdb: Clear GDB_PS on 64-bit · 16363019
      Brian Gerst authored
      switch_to() no longer saves EFLAGS, so it's bogus to look for it on the
      stack.  Set it to zero like 32-bit.
      Signed-off-by: default avatarBrian Gerst <brgerst@gmail.com>
      Reviewed-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jason Wessel <jason.wessel@windriver.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/1471106302-10159-3-git-send-email-brgerst@gmail.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      16363019
    • Brian Gerst's avatar
      sched/x86/32, kgdb: Don't use thread.ip in sleeping_thread_to_gdb_regs() · 4e047aa7
      Brian Gerst authored
      Match 64-bit and set gdb_regs[GDB_PC] to zero.  thread.ip is always the
      same point in the scheduler (except for newly forked processes), and will
      be removed in a future patch.
      Signed-off-by: default avatarBrian Gerst <brgerst@gmail.com>
      Reviewed-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jason Wessel <jason.wessel@windriver.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/1471106302-10159-2-git-send-email-brgerst@gmail.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      4e047aa7
    • Josh Poimboeuf's avatar
      x86/dumpstack/ftrace: Don't print unreliable addresses in print_context_stack_bp() · 13e25bab
      Josh Poimboeuf authored
      When function graph tracing is enabled, print_context_stack_bp() can
      report return_to_handler() as an unreliable address, which is confusing
      and misleading: return_to_handler() is really only useful as a hint for
      debugging, whereas print_context_stack_bp() users only care about the
      actual 'reliable' call path.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/c51aef578d8027791b38d2ad9bac0c7f499fde91.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      13e25bab
    • Josh Poimboeuf's avatar
      x86/dumpstack/ftrace: Mark function graph handler function as unreliable · 6f727b84
      Josh Poimboeuf authored
      When function graph tracing is enabled for a function, its return
      address on the stack is replaced with the address of an ftrace handler
      (return_to_handler).
      
      Currently 'return_to_handler' can be reported as reliable.  That's not
      ideal, and can actually be misleading.  When saving or dumping the
      stack, you normally only care about what led up to that point (the call
      path), rather than what will happen in the future (the return path).
      
      That's especially true in the non-oops stack trace case, which isn't
      used for debugging.  For example, in a perf profiling operation,
      reporting return_to_handler() in the trace would just be confusing.
      
      And in the oops case, where debugging is important, "unreliable" is also
      more appropriate there because it serves as a hint that graph tracing
      was involved, instead of trying to imply that return_to_handler() was
      the real caller.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/f8af15749c7d632d3e7f815995831d5b7f82950d.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6f727b84
    • Josh Poimboeuf's avatar
      ftrace/x86: Implement HAVE_FUNCTION_GRAPH_RET_ADDR_PTR · 471bd10f
      Josh Poimboeuf authored
      Use the more reliable version of ftrace_graph_ret_addr() so we no longer
      have to worry about the unwinder getting out of sync with the function
      graph ret_stack index, which can happen if the unwinder skips any frames
      before calling ftrace_graph_ret_addr().
      
      This fixes this issue (and several others like it):
      
        $ cat /proc/self/stack
        [<ffffffff810489a2>] save_stack_trace_tsk+0x22/0x40
        [<ffffffff81311a89>] proc_pid_stack+0xb9/0x110
        [<ffffffff813127c4>] proc_single_show+0x54/0x80
        [<ffffffff812be088>] seq_read+0x108/0x3e0
        [<ffffffff812923d7>] __vfs_read+0x37/0x140
        [<ffffffff812929d9>] vfs_read+0x99/0x140
        [<ffffffff81293f28>] SyS_read+0x58/0xc0
        [<ffffffff818af97c>] entry_SYSCALL_64_fastpath+0x1f/0xbd
        [<ffffffffffffffff>] 0xffffffffffffffff
      
        $ echo function_graph > /sys/kernel/debug/tracing/current_tracer
      
        $ cat /proc/self/stack
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff810394cc>] print_context_stack+0xfc/0x100
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff8103891b>] dump_trace+0x12b/0x350
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff810489a2>] save_stack_trace_tsk+0x22/0x40
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff81311a89>] proc_pid_stack+0xb9/0x110
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff813127c4>] proc_single_show+0x54/0x80
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff812be088>] seq_read+0x108/0x3e0
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff812923d7>] __vfs_read+0x37/0x140
        [<ffffffff818b2428>] return_to_handler+0x0/0x27
        [<ffffffff812929d9>] vfs_read+0x99/0x140
        [<ffffffffffffffff>] 0xffffffffffffffff
      
      Enabling function graph tracing causes the stack trace to change in two
      ways:
      
      First, the real call addresses are confusingly interspersed with
      'return_to_handler' addresses.  This issue will be fixed by the next
      patch.
      
      Second, the stack trace is offset by two frames, because the unwinder
      skipped the first two frames and got out of sync with the ret_stack
      index.  This patch fixes this issue.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/a6d623e36f8d08f9a17bd74d804d201177a23afd.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      471bd10f
    • Josh Poimboeuf's avatar
      x86/dumpstack/ftrace: Convert dump_trace() callbacks to use ftrace_graph_ret_addr() · 408fe5de
      Josh Poimboeuf authored
      Convert print_context_stack() and print_context_stack_bp() to use the
      arch-independent ftrace_graph_ret_addr() helper.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/56ec97cafc1bf2e34d1119e6443d897db406da86.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      408fe5de
    • Josh Poimboeuf's avatar
      ftrace: Add ftrace_graph_ret_addr() stack unwinding helpers · 223918e3
      Josh Poimboeuf authored
      When function graph tracing is enabled for a function, ftrace modifies
      the stack by replacing the original return address with the address of a
      hook function (return_to_handler).
      
      Stack unwinders need a way to get the original return address.  Add an
      arch-independent helper function for that named ftrace_graph_ret_addr().
      
      This adds two variations of the function: one depends on
      HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, and the other relies on an index state
      variable.
      
      The former is recommended because, in some cases, the latter can cause
      problems when the unwinder skips stack frames.  It can get out of sync
      with the ret_stack index and wrong addresses can be reported for the
      stack trace.
      
      Once all arches have been ported to use
      HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, we can get rid of the distinction.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/36bd90f762fc5e5af3929e3797a68a64906421cf.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      223918e3
    • Josh Poimboeuf's avatar
      ftrace: Add return address pointer to ftrace_ret_stack · 9a7c348b
      Josh Poimboeuf authored
      Storing this value will help prevent unwinders from getting out of sync
      with the function graph tracer ret_stack.  Now instead of needing a
      stateful iterator, they can compare the return address pointer to find
      the right ret_stack entry.
      
      Note that an array of 50 ftrace_ret_stack structs is allocated for every
      task.  So when an arch implements this, it will add either 200 or 400
      bytes of memory usage per task (depending on whether it's a 32-bit or
      64-bit platform).
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/a95cfcc39e8f26b89a430c56926af0bb217bc0a1.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9a7c348b
    • Josh Poimboeuf's avatar
      ftrace: Only allocate the ret_stack 'fp' field when needed · daa460a8
      Josh Poimboeuf authored
      This saves some memory when HAVE_FUNCTION_GRAPH_FP_TEST isn't defined.
      On x86_64 with newer versions of gcc which have -mfentry, it saves 400
      bytes per task.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/5c7747d9ea7b5cb47ef0a8ce8a6cea6bf7aa94bf.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      daa460a8
    • Josh Poimboeuf's avatar
      ftrace: Remove CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST from config · e4a744ef
      Josh Poimboeuf authored
      Make HAVE_FUNCTION_GRAPH_FP_TEST a normal define, independent from
      kconfig.  This removes some config file pollution and simplifies the
      checking for the fp test.
      Suggested-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      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: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/2c4e5f05054d6d367f702fd153af7a0109dd5c81.1471607358.git.jpoimboe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      e4a744ef
    • Andy Lutomirski's avatar
      x86/mm/64: Enable vmapped stacks (CONFIG_HAVE_ARCH_VMAP_STACK=y) · e37e43a4
      Andy Lutomirski authored
      This allows x86_64 kernels to enable vmapped stacks by setting
      HAVE_ARCH_VMAP_STACK=y - which enables the CONFIG_VMAP_STACK=y
      high level Kconfig option.
      
      There are a couple of interesting bits:
      
      First, x86 lazily faults in top-level paging entries for the vmalloc
      area.  This won't work if we get a page fault while trying to access
      the stack: the CPU will promote it to a double-fault and we'll die.
      To avoid this problem, probe the new stack when switching stacks and
      forcibly populate the pgd entry for the stack when switching mms.
      
      Second, once we have guard pages around the stack, we'll want to
      detect and handle stack overflow.
      
      I didn't enable it on x86_32.  We'd need to rework the double-fault
      code a bit and I'm concerned about running out of vmalloc virtual
      addresses under some workloads.
      
      This patch, by itself, will behave somewhat erratically when the
      stack overflows while RSP is still more than a few tens of bytes
      above the bottom of the stack.  Specifically, we'll get #PF and make
      it to no_context and them oops without reliably triggering a
      double-fault, and no_context doesn't know about stack overflows.
      The next patch will improve that case.
      
      Thank you to Nadav and Brian for helping me pay enough attention to
      the SDM to hopefully get this right.
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      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: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Nadav Amit <nadav.amit@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/c88f3e2920b18e6cc621d772a04a62c06869037e.1470907718.git.luto@kernel.org
      [ Minor edits. ]
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      e37e43a4
    • Andy Lutomirski's avatar
      dma-api: Teach the "DMA-from-stack" check about vmapped stacks · b4a0f533
      Andy Lutomirski authored
      If we're using CONFIG_VMAP_STACK=y and we manage to point an sg entry
      at the stack, then either the sg page will be in highmem or sg_virt()
      will return the direct-map alias.  In neither case will the existing
      check_for_stack() implementation realize that it's a stack page.
      
      Fix it by explicitly checking for stack pages.
      
      This has no effect by itself.  It's broken out for ease of review.
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      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: Josh Poimboeuf <jpoimboe@redhat.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/448460622731312298bf19dcbacb1606e75de7a9.1470907718.git.luto@kernel.org
      [ Minor edits. ]
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      b4a0f533
    • Andy Lutomirski's avatar
      fork: Add generic vmalloced stack support · ba14a194
      Andy Lutomirski authored
      If CONFIG_VMAP_STACK=y is selected, kernel stacks are allocated with
      __vmalloc_node_range().
      
      Grsecurity has had a similar feature (called GRKERNSEC_KSTACKOVERFLOW=y)
      for a long time.
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      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/14c07d4fd173a5b117f51e8b939f9f4323e39899.1470907718.git.luto@kernel.org
      [ Minor edits. ]
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      ba14a194
    • Ingo Molnar's avatar
      eb4e8410
    • Borislav Petkov's avatar
      x86/entry: Remove outdated comment about SYSCALL targets · 556b6723
      Borislav Petkov authored
      The comment probably meant some old AMD64 incarnation which most likely
      never saw the light of day. STAR and LSTAR are two different registers
      and STAR sets CS/SS(DS) selectors for *all* modes, not only 32-bit.
      
      So simply remove that comment.
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Andy Lutomirski <luto@kernel.org>
      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: Josh Poimboeuf <jpoimboe@redhat.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/20160823172356.15879-1-bp@alien8.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      556b6723
  2. 21 Aug, 2016 3 commits
  3. 20 Aug, 2016 2 commits
    • Helge Deller's avatar
      parisc: Fix order of EREFUSED define in errno.h · 3eb53b20
      Helge Deller authored
      When building gccgo in userspace, errno.h gets parsed and the go include file
      sysinfo.go is generated.
      
      Since EREFUSED is defined to the same value as ECONNREFUSED, and ECONNREFUSED
      is defined later on in errno.h, this leads to go complaining that EREFUSED
      isn't defined yet.
      
      Fix this trivial problem by moving the define of EREFUSED down after
      ECONNREFUSED in errno.h (and clean up the indenting while touching this line).
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Cc: stable@vger.kernel.org
      3eb53b20
    • Helge Deller's avatar
      parisc: Fix automatic selection of cr16 clocksource · ae141830
      Helge Deller authored
      Commit 54b66800 (parisc: Add native high-resolution sched_clock()
      implementation) added support to use the CPU-internal cr16 counters as reliable
      clocksource with the help of HAVE_UNSTABLE_SCHED_CLOCK.
      
      Sadly the commit missed to remove the hack which prevented cr16 to become the
      default clocksource even on SMP systems.
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Cc: stable@vger.kernel.org # 4.7+
      ae141830
  4. 19 Aug, 2016 10 commits
    • Linus Torvalds's avatar
      Make the hardened user-copy code depend on having a hardened allocator · 6040e576
      Linus Torvalds authored
      The kernel test robot reported a usercopy failure in the new hardened
      sanity checks, due to a page-crossing copy of the FPU state into the
      task structure.
      
      This happened because the kernel test robot was testing with SLOB, which
      doesn't actually do the required book-keeping for slab allocations, and
      as a result the hardening code didn't realize that the task struct
      allocation was one single allocation - and the sanity checks fail.
      
      Since SLOB doesn't even claim to support hardening (and you really
      shouldn't use it), the straightforward solution is to just make the
      usercopy hardening code depend on the allocator supporting it.
      Reported-by: default avatarkernel test robot <xiaolong.ye@intel.com>
      Cc: Kees Cook <keescook@chromium.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      6040e576
    • Linus Torvalds's avatar
      Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux · 8cc9dddd
      Linus Torvalds authored
      Pull i2c fixes from Wolfram Sang:
       "I2C has some pretty standard driver bugfixes and one minor cleanup"
      
      * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
        i2c: meson: Use complete() instead of complete_all()
        i2c: brcmstb: Use complete() instead of complete_all()
        i2c: bcm-kona: Use complete() instead of complete_all()
        i2c: bcm-iproc: Use complete() instead of complete_all()
        i2c: at91: fix support of the "alternative command" feature
        i2c: ocores: add missed clk_disable_unprepare() on failure paths
        i2c: cros-ec-tunnel: Fix usage of cros_ec_cmd_xfer()
        i2c: mux: demux-pinctrl: properly roll back when adding adapter fails
      8cc9dddd
    • Linus Torvalds's avatar
      Merge tag 'dm-4.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm · 43f4d36c
      Linus Torvalds authored
      Pull device mapper fixes from Mike Snitzer:
      
       - a stable fix for DM round robin multipath path selector to disable
         preemption before using this_cpu_ptr()
      
       - a slight increase in DM crypt's mempool reserves to make swap ontop
         of DM crypt more performant
      
       - a few DM raid fixes to issues found while testing changes that were
         merged in v4.8-rc1
      
      * tag 'dm-4.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
        dm raid: support raid0 with missing metadata devices
        dm raid: enhance attempt_restore_of_faulty_devices() to support more devices
        dm raid: fix restoring of failed devices regression
        dm raid: fix frozen recovery regression
        dm crypt: increase mempool reserve to better support swapping
        dm round robin: do not use this_cpu_ptr() without having preemption disabled
      43f4d36c
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · b2848792
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "Six fairly small fixes.  The ipr, mpt3sas and ses ones all trigger
        oopses.  The megaraid one fixes an attach failure on io mapped only
        cards, the fcoe one is an obvious problem in the error path and the
        aacraid one is a theoretical security issue (ability to trick the
        kernel into a buffer overrun)"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        ses: Fix racy cleanup of /sys in remove_dev()
        mpt3sas: Fix resume on WarpDrive flash cards
        ipr: Fix sync scsi scan
        megaraid_sas: Fix probing cards without io port
        aacraid: Check size values after double-fetch from user
        fcoe: Use kfree_skb() instead of kfree()
      b2848792
    • Linus Torvalds's avatar
      Merge tag 'usb-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb · 080ebb15
      Linus Torvalds authored
      Pull USB fixes from Greg KH:
       "Here are a number of USB fixes for reported issues for your tree.
      
        The normal amount of gadget fixes, xhci fixes, new device ids, and a
        few other minor things.  All of them have been in linux-next for a
        while, the full details are in the shortlog below"
      
      * tag 'usb-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (43 commits)
        xhci: don't dereference a xhci member after removing xhci
        usb: xhci: Fix panic if disconnect
        xhci: really enqueue zero length TRBs.
        xhci: always handle "Command Ring Stopped" events
        cdc-acm: fix wrong pipe type on rx interrupt xfers
        usb: misc: usbtest: add fix for driver hang
        usb: dwc3: gadget: stop processing on HWO set
        usb: dwc3: don't set last bit for ISOC endpoints
        usb: gadget: rndis: free response queue during REMOTE_NDIS_RESET_MSG
        usb: udc: core: fix error handling
        usb: gadget: fsl_qe_udc: off by one in setup_received_handle()
        usb/gadget: fix gadgetfs aio support.
        usb: gadget: composite: Fix return value in case of error
        usb: gadget: uvc: Fix return value in case of error
        usb: gadget: fix check in sync read from ep in gadgetfs
        usb: misc: usbtest: usbtest_do_ioctl may return positive integer
        usb: dwc3: fix missing platform_set_drvdata() in dwc3_of_simple_probe()
        usb: phy: omap-otg: Fix missing platform_set_drvdata() in omap_otg_probe()
        usb: gadget: configfs: add mutex lock before unregister gadget
        usb: gadget: u_ether: fix dereference after null check coverify warning
        ...
      080ebb15
    • Linus Torvalds's avatar
      Merge tag 'xfs-iomap-for-linus-4.8-rc3' of... · a8414fa3
      Linus Torvalds authored
      Merge tag 'xfs-iomap-for-linus-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
      
      Pull xfs and iomap fixes from Dave Chinner:
       "Changes in this update:
      
        Regression fixes for XFS changes introduce in 4.8-rc1:
         - buffer IO accounting assert failure
         - ENOSPC block accounting reservation issue
         - DAX IO path page cache invalidation fix
         - rmapbt on-disk block count in agf
         - correct classification of rmap block type when updating AGFL.
         - iomap support for attribute fork mapping
      
        Regression fixes for iomap infrastructure in 4.8-rc1:
         - fiemap: honor FIEMAP_FLAG_SYNC
         - fiemap: implement FIEMAP_FLAG_XATTR support to fix XFS regression
         - make mark_page_accessed and pagefault_disable usage consistent with
           other IO paths"
      
      * tag 'xfs-iomap-for-linus-4.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
        xfs: remove OWN_AG rmap when allocating a block from the AGFL
        xfs: (re-)implement FIEMAP_FLAG_XATTR
        xfs: simplify xfs_file_iomap_begin
        iomap: mark ->iomap_end as optional
        iomap: prepare iomap_fiemap for attribute mappings
        iomap: fiemap should honor the FIEMAP_FLAG_SYNC flag
        iomap: remove superflous pagefault_disable from iomap_write_actor
        iomap: remove superflous mark_page_accessed from iomap_write_actor
        xfs: store rmapbt block count in the AGF
        xfs: don't invalidate whole file on DAX read/write
        xfs: fix bogus space reservation in xfs_iomap_write_allocate
        xfs: don't assert fail on non-async buffers on ioacct decrement
      a8414fa3
    • Linus Torvalds's avatar
      Merge tag 'hwmon-for-linus-v4.8-rc2' of... · 3f318b3c
      Linus Torvalds authored
      Merge tag 'hwmon-for-linus-v4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
      
      Pull hwmon fixes from Guenter Roeck:
       "Fix a bug in it87 driver and URLs in ftsteutates driver"
      
      * tag 'hwmon-for-linus-v4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
        hwmon: (ftsteutates) Correct ftp urls in driver documentation
        hwmon: (it87) Features mask must be 32 bit wide
      3f318b3c
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-for-4.8-rc3-2' of git://people.freedesktop.org/~airlied/linux · 952b159f
      Linus Torvalds authored
      Pull more drm fixes from Dave Airlie:
       "Daniel pointed out I'd missed some i915 fixes, and I also found a
        single etnaviv fix I missed.
      
        So here they are"
      
      * tag 'drm-fixes-for-4.8-rc3-2' of git://people.freedesktop.org/~airlied/linux:
        drm/etnaviv: take GPU lock later in the submit process
        drm/i915: Fix modeset handling during gpu reset, v5.
        drm/i915: fix aliasing_ppgtt leak
        drm/i915: fix WaInsertDummyPushConstPs
        drm/i915: Fix iboost setting for SKL Y/U DP DDI buffer translation entry 2
        drm/i915/gen9: Give one extra block per line for SKL plane WM calculations
        drm/i915: Acquire audio powerwell for HD-Audio registers
        drm/i915: Add missing rpm wakelock to GGTT pread
        drm/i915/fbc: FBC causes display flicker when VT-d is enabled on Skylake
        drm/i915: Clean up the extra RPM ref on CHV with i915.enable_rc6=0
        drm/i915: Program iboost settings for HDMI/DVI on SKL
        drm/i915: Fix iboost setting for DDI with 4 lanes on SKL
        drm/i915: Handle ENOSPC after failing to insert a mappable node
        drm/i915: Flush GT idle status upon reset
      952b159f
    • Linus Torvalds's avatar
      Merge tag 'devicetree-fixes-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux · d8298d26
      Linus Torvalds authored
      Pull DeviceTree fixes from Rob Herring:
      
       - a couple of DT node ref counting fixes
      
       - fix __unflatten_device_tree for PPC PCI hotplug case
      
       - rework marking irq controllers as OF_POPULATED in cases where real
         driver is used.
      
       - disable of_platform_default_populate_init on PPC.  The change in
         initcall order causes problems which need to be sorted out later.
      
      * tag 'devicetree-fixes-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
        of: fix reference counting in of_graph_get_endpoint_by_regs
        of/platform: disable the of_platform_default_populate_init() for all the ppc boards
        ARM: imx6: mark GPC node as not populated after irq init to probe pm domain driver
        of/irq: Mark interrupt controllers as populated before initialisation
        drivers/of: Validate device node in __unflatten_device_tree()
        of: Delete an unnecessary check before the function call "of_node_put"
      d8298d26
    • Linus Torvalds's avatar
      Merge tag '4.8-doc-fixes' of git://git.lwn.net/linux · 5cae6fe2
      Linus Torvalds authored
      Pull documentation fixes from Jonathan Corbet:
       "Three small fixes for Sphinx-formatted documentation generation"
      
      * tag '4.8-doc-fixes' of git://git.lwn.net/linux:
        doc-rst: customize RTD theme, drop padding of inline literal
        docs: kernel-documentation: remove some highlight directives
        docs: Set the Sphinx default highlight language to "guess"
      5cae6fe2
  5. 18 Aug, 2016 10 commits