1. 13 May, 2013 10 commits
    • Yinghai Lu's avatar
      PCI / ACPI: Don't query OSC support with all possible controls · c08f24e2
      Yinghai Lu authored
      commit 545d6e18 upstream.
      
      Found problem on system that firmware that could handle pci aer.
      Firmware get error reporting after pci injecting error, before os boots.
      But after os boots, firmware can not get report anymore, even pci=noaer
      is passed.
      
      Root cause: BIOS _OSC has problem with query bit checking.
      It turns out that BIOS vendor is copying example code from ACPI Spec.
      In ACPI Spec 5.0, page 290:
      
      	If (Not(And(CDW1,1))) // Query flag clear?
      	{	// Disable GPEs for features granted native control.
      		If (And(CTRL,0x01)) // Hot plug control granted?
      		{
      			Store(0,HPCE) // clear the hot plug SCI enable bit
      			Store(1,HPCS) // clear the hot plug SCI status bit
      		}
      	...
      	}
      
      When Query flag is set, And(CDW1,1) will be 1, Not(1) will return 0xfffffffe.
      So it will get into code path that should be for control set only.
      BIOS acpi code should be changed to "If (LEqual(And(CDW1,1), 0)))"
      
      Current kernel code is using _OSC query to notify firmware about support
      from OS and then use _OSC to set control bits.
      During query support, current code is using all possible controls.
      So will execute code that should be only for control set stage.
      
      That will have problem when pci=noaer or aer firmware_first is used.
      As firmware have that control set for os aer already in query support stage,
      but later will not os aer handling.
      
      We should avoid passing all possible controls, just use osc_control_set
      instead.
      That should workaround BIOS bugs with affected systems on the field
      as more bios vendors are copying sample code from ACPI spec.
      Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      c08f24e2
    • Li Zefan's avatar
      cgroup: fix an off-by-one bug which may trigger BUG_ON() · f596ca6c
      Li Zefan authored
      commit 3ac1707a upstream.
      
      The 3rd parameter of flex_array_prealloc() is the number of elements,
      not the index of the last element.
      
      The effect of the bug is, when opening cgroup.procs, a flex array will
      be allocated and all elements of the array is allocated with
      GFP_KERNEL flag, but the last one is GFP_ATOMIC, and if we fail to
      allocate memory for it, it'll trigger a BUG_ON().
      Signed-off-by: default avatarLi Zefan <lizefan@huawei.com>
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      f596ca6c
    • Stephan Schreiber's avatar
      Wrong asm register contraints in the kvm implementation · 6d895982
      Stephan Schreiber authored
      commit de53e9ca upstream.
      
      The Linux Kernel contains some inline assembly source code which has
      wrong asm register constraints in arch/ia64/kvm/vtlb.c.
      
      I observed this on Kernel 3.2.35 but it is also true on the most
      recent Kernel 3.9-rc1.
      
      File arch/ia64/kvm/vtlb.c:
      
      u64 guest_vhpt_lookup(u64 iha, u64 *pte)
      {
      	u64 ret;
      	struct thash_data *data;
      
      	data = __vtr_lookup(current_vcpu, iha, D_TLB);
      	if (data != NULL)
      		thash_vhpt_insert(current_vcpu, data->page_flags,
      			data->itir, iha, D_TLB);
      
      	asm volatile (
      			"rsm psr.ic|psr.i;;"
      			"srlz.d;;"
      			"ld8.s r9=[%1];;"
      			"tnat.nz p6,p7=r9;;"
      			"(p6) mov %0=1;"
      			"(p6) mov r9=r0;"
      			"(p7) extr.u r9=r9,0,53;;"
      			"(p7) mov %0=r0;"
      			"(p7) st8 [%2]=r9;;"
      			"ssm psr.ic;;"
      			"srlz.d;;"
      			"ssm psr.i;;"
      			"srlz.d;;"
      			: "=r"(ret) : "r"(iha), "r"(pte):"memory");
      
      	return ret;
      }
      
      The list of output registers is
      			: "=r"(ret) : "r"(iha), "r"(pte):"memory");
      The constraint "=r" means that the GCC has to maintain that these vars
      are in registers and contain valid info when the program flow leaves
      the assembly block (output registers).
      But "=r" also means that GCC can put them in registers that are used
      as input registers. Input registers are iha, pte on the example.
      If the predicate p7 is true, the 8th assembly instruction
      			"(p7) mov %0=r0;"
      is the first one which writes to a register which is maintained by the
      register constraints; it sets %0. %0 means the first register operand;
      it is ret here.
      This instruction might overwrite the %2 register (pte) which is needed
      by the next instruction:
      			"(p7) st8 [%2]=r9;;"
      Whether it really happens depends on how GCC decides what registers it
      uses and how it optimizes the code.
      
      The attached patch  fixes the register operand constraints in
      arch/ia64/kvm/vtlb.c.
      The register constraints should be
      			: "=&r"(ret) : "r"(iha), "r"(pte):"memory");
      The & means that GCC must not use any of the input registers to place
      this output register in.
      
      This is Debian bug#702639
      (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=702639).
      
      The patch is applicable on Kernel 3.9-rc1, 3.2.35 and many other versions.
      Signed-off-by: default avatarStephan Schreiber <info@fs-driver.org>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      6d895982
    • Stephan Schreiber's avatar
      Wrong asm register contraints in the futex implementation · b5789c66
      Stephan Schreiber authored
      commit 136f39dd upstream.
      
      The Linux Kernel contains some inline assembly source code which has
      wrong asm register constraints in arch/ia64/include/asm/futex.h.
      
      I observed this on Kernel 3.2.23 but it is also true on the most
      recent Kernel 3.9-rc1.
      
      File arch/ia64/include/asm/futex.h:
      
      static inline int
      futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
      			      u32 oldval, u32 newval)
      {
      	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
      		return -EFAULT;
      
      	{
      		register unsigned long r8 __asm ("r8");
      		unsigned long prev;
      		__asm__ __volatile__(
      			"	mf;;					\n"
      			"	mov %0=r0				\n"
      			"	mov ar.ccv=%4;;				\n"
      			"[1:]	cmpxchg4.acq %1=[%2],%3,ar.ccv		\n"
      			"	.xdata4 \"__ex_table\", 1b-., 2f-.	\n"
      			"[2:]"
      			: "=r" (r8), "=r" (prev)
      			: "r" (uaddr), "r" (newval),
      			  "rO" ((long) (unsigned) oldval)
      			: "memory");
      		*uval = prev;
      		return r8;
      	}
      }
      
      The list of output registers is
      			: "=r" (r8), "=r" (prev)
      The constraint "=r" means that the GCC has to maintain that these vars
      are in registers and contain valid info when the program flow leaves
      the assembly block (output registers).
      But "=r" also means that GCC can put them in registers that are used
      as input registers. Input registers are uaddr, newval, oldval on the
      example.
      The second assembly instruction
      			"	mov %0=r0				\n"
      is the first one which writes to a register; it sets %0 to 0. %0 means
      the first register operand; it is r8 here. (The r0 is read-only and
      always 0 on the Itanium; it can be used if an immediate zero value is
      needed.)
      This instruction might overwrite one of the other registers which are
      still needed.
      Whether it really happens depends on how GCC decides what registers it
      uses and how it optimizes the code.
      
      The objdump utility can give us disassembly.
      The futex_atomic_cmpxchg_inatomic() function is inline, so we have to
      look for a module that uses the funtion. This is the
      cmpxchg_futex_value_locked() function in
      kernel/futex.c:
      
      static int cmpxchg_futex_value_locked(u32 *curval, u32 __user *uaddr,
      				      u32 uval, u32 newval)
      {
      	int ret;
      
      	pagefault_disable();
      	ret = futex_atomic_cmpxchg_inatomic(curval, uaddr, uval, newval);
      	pagefault_enable();
      
      	return ret;
      }
      
      Now the disassembly. At first from the Kernel package 3.2.23 which has
      been compiled with GCC 4.4, remeber this Kernel seemed to work:
      objdump -d linux-3.2.23/debian/build/build_ia64_none_mckinley/kernel/futex.o
      
      0000000000000230 <cmpxchg_futex_value_locked>:
            230:	0b 18 80 1b 18 21 	[MMI]       adds r3=3168,r13;;
            236:	80 40 0d 00 42 00 	            adds r8=40,r3
            23c:	00 00 04 00       	            nop.i 0x0;;
            240:	0b 50 00 10 10 10 	[MMI]       ld4 r10=[r8];;
            246:	90 08 28 00 42 00 	            adds r9=1,r10
            24c:	00 00 04 00       	            nop.i 0x0;;
            250:	09 00 00 00 01 00 	[MMI]       nop.m 0x0
            256:	00 48 20 20 23 00 	            st4 [r8]=r9
            25c:	00 00 04 00       	            nop.i 0x0;;
            260:	08 10 80 06 00 21 	[MMI]       adds r2=32,r3
            266:	00 00 00 02 00 00 	            nop.m 0x0
            26c:	02 08 f1 52       	            extr.u r16=r33,0,61
            270:	05 40 88 00 08 e0 	[MLX]       addp4 r8=r34,r0
            276:	ff ff 0f 00 00 e0 	            movl r15=0xfffffffbfff;;
            27c:	f1 f7 ff 65
            280:	09 70 00 04 18 10 	[MMI]       ld8 r14=[r2]
            286:	00 00 00 02 00 c0 	            nop.m 0x0
            28c:	f0 80 1c d0       	            cmp.ltu p6,p7=r15,r16;;
            290:	08 40 fc 1d 09 3b 	[MMI]       cmp.eq p8,p9=-1,r14
            296:	00 00 00 02 00 40 	            nop.m 0x0
            29c:	e1 08 2d d0       	            cmp.ltu p10,p11=r14,r33
            2a0:	56 01 10 00 40 10 	[BBB] (p10) br.cond.spnt.few 2e0
      <cmpxchg_futex_value_locked+0xb0>
            2a6:	02 08 00 80 21 03 	      (p08) br.cond.dpnt.few 2b0
      <cmpxchg_futex_value_locked+0x80>
            2ac:	40 00 00 41       	      (p06) br.cond.spnt.few 2e0
      <cmpxchg_futex_value_locked+0xb0>
            2b0:	0a 00 00 00 22 00 	[MMI]       mf;;
            2b6:	80 00 00 00 42 00 	            mov r8=r0
            2bc:	00 00 04 00       	            nop.i 0x0
            2c0:	0b 00 20 40 2a 04 	[MMI]       mov.m ar.ccv=r8;;
            2c6:	10 1a 85 22 20 00 	            cmpxchg4.acq r33=[r33],r35,ar.ccv
            2cc:	00 00 04 00       	            nop.i 0x0;;
            2d0:	10 00 84 40 90 11 	[MIB]       st4 [r32]=r33
            2d6:	00 00 00 02 00 00 	            nop.i 0x0
            2dc:	20 00 00 40       	            br.few 2f0
      <cmpxchg_futex_value_locked+0xc0>
            2e0:	09 40 c8 f9 ff 27 	[MMI]       mov r8=-14
            2e6:	00 00 00 02 00 00 	            nop.m 0x0
            2ec:	00 00 04 00       	            nop.i 0x0;;
            2f0:	0b 58 20 1a 19 21 	[MMI]       adds r11=3208,r13;;
            2f6:	20 01 2c 20 20 00 	            ld4 r18=[r11]
            2fc:	00 00 04 00       	            nop.i 0x0;;
            300:	0b 88 fc 25 3f 23 	[MMI]       adds r17=-1,r18;;
            306:	00 88 2c 20 23 00 	            st4 [r11]=r17
            30c:	00 00 04 00       	            nop.i 0x0;;
            310:	11 00 00 00 01 00 	[MIB]       nop.m 0x0
            316:	00 00 00 02 00 80 	            nop.i 0x0
            31c:	08 00 84 00       	            br.ret.sptk.many b0;;
      
      The lines
            2b0:	0a 00 00 00 22 00 	[MMI]       mf;;
            2b6:	80 00 00 00 42 00 	            mov r8=r0
            2bc:	00 00 04 00       	            nop.i 0x0
            2c0:	0b 00 20 40 2a 04 	[MMI]       mov.m ar.ccv=r8;;
            2c6:	10 1a 85 22 20 00 	            cmpxchg4.acq r33=[r33],r35,ar.ccv
            2cc:	00 00 04 00       	            nop.i 0x0;;
      are the instructions of the assembly block.
      The line
            2b6:	80 00 00 00 42 00 	            mov r8=r0
      sets the r8 register to 0 and after that
            2c0:	0b 00 20 40 2a 04 	[MMI]       mov.m ar.ccv=r8;;
      prepares the 'oldvalue' for the cmpxchg but it takes it from r8. This
      is wrong.
      What happened here is what I explained above: An input register is
      overwritten which is still needed.
      The register operand constraints in futex.h are wrong.
      
      (The problem doesn't occur when the Kernel is compiled with GCC 4.6.)
      
      The attached patch fixes the register operand constraints in futex.h.
      The code after patching of it:
      
      static inline int
      futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
      			      u32 oldval, u32 newval)
      {
      	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
      		return -EFAULT;
      
      	{
      		register unsigned long r8 __asm ("r8") = 0;
      		unsigned long prev;
      		__asm__ __volatile__(
      			"	mf;;					\n"
      			"	mov ar.ccv=%4;;				\n"
      			"[1:]	cmpxchg4.acq %1=[%2],%3,ar.ccv		\n"
      			"	.xdata4 \"__ex_table\", 1b-., 2f-.	\n"
      			"[2:]"
      			: "+r" (r8), "=&r" (prev)
      			: "r" (uaddr), "r" (newval),
      			  "rO" ((long) (unsigned) oldval)
      			: "memory");
      		*uval = prev;
      		return r8;
      	}
      }
      
      I also initialized the 'r8' var with the C programming language.
      The _asm qualifier on the definition of the 'r8' var forces GCC to use
      the r8 processor register for it.
      I don't believe that we should use inline assembly for zeroing out a
      local variable.
      The constraint is
      "+r" (r8)
      what means that it is both an input register and an output register.
      Note that the page fault handler will modify the r8 register which
      will be the return value of the function.
      The real fix is
      "=&r" (prev)
      The & means that GCC must not use any of the input registers to place
      this output register in.
      
      Patched the Kernel 3.2.23 and compiled it with GCC4.4:
      
      0000000000000230 <cmpxchg_futex_value_locked>:
            230:	0b 18 80 1b 18 21 	[MMI]       adds r3=3168,r13;;
            236:	80 40 0d 00 42 00 	            adds r8=40,r3
            23c:	00 00 04 00       	            nop.i 0x0;;
            240:	0b 50 00 10 10 10 	[MMI]       ld4 r10=[r8];;
            246:	90 08 28 00 42 00 	            adds r9=1,r10
            24c:	00 00 04 00       	            nop.i 0x0;;
            250:	09 00 00 00 01 00 	[MMI]       nop.m 0x0
            256:	00 48 20 20 23 00 	            st4 [r8]=r9
            25c:	00 00 04 00       	            nop.i 0x0;;
            260:	08 10 80 06 00 21 	[MMI]       adds r2=32,r3
            266:	20 12 01 10 40 00 	            addp4 r34=r34,r0
            26c:	02 08 f1 52       	            extr.u r16=r33,0,61
            270:	05 40 00 00 00 e1 	[MLX]       mov r8=r0
            276:	ff ff 0f 00 00 e0 	            movl r15=0xfffffffbfff;;
            27c:	f1 f7 ff 65
            280:	09 70 00 04 18 10 	[MMI]       ld8 r14=[r2]
            286:	00 00 00 02 00 c0 	            nop.m 0x0
            28c:	f0 80 1c d0       	            cmp.ltu p6,p7=r15,r16;;
            290:	08 40 fc 1d 09 3b 	[MMI]       cmp.eq p8,p9=-1,r14
            296:	00 00 00 02 00 40 	            nop.m 0x0
            29c:	e1 08 2d d0       	            cmp.ltu p10,p11=r14,r33
            2a0:	56 01 10 00 40 10 	[BBB] (p10) br.cond.spnt.few 2e0
      <cmpxchg_futex_value_locked+0xb0>
            2a6:	02 08 00 80 21 03 	      (p08) br.cond.dpnt.few 2b0
      <cmpxchg_futex_value_locked+0x80>
            2ac:	40 00 00 41       	      (p06) br.cond.spnt.few 2e0
      <cmpxchg_futex_value_locked+0xb0>
            2b0:	0b 00 00 00 22 00 	[MMI]       mf;;
            2b6:	00 10 81 54 08 00 	            mov.m ar.ccv=r34
            2bc:	00 00 04 00       	            nop.i 0x0;;
            2c0:	09 58 8c 42 11 10 	[MMI]       cmpxchg4.acq r11=[r33],r35,ar.ccv
            2c6:	00 00 00 02 00 00 	            nop.m 0x0
            2cc:	00 00 04 00       	            nop.i 0x0;;
            2d0:	10 00 2c 40 90 11 	[MIB]       st4 [r32]=r11
            2d6:	00 00 00 02 00 00 	            nop.i 0x0
            2dc:	20 00 00 40       	            br.few 2f0
      <cmpxchg_futex_value_locked+0xc0>
            2e0:	09 40 c8 f9 ff 27 	[MMI]       mov r8=-14
            2e6:	00 00 00 02 00 00 	            nop.m 0x0
            2ec:	00 00 04 00       	            nop.i 0x0;;
            2f0:	0b 88 20 1a 19 21 	[MMI]       adds r17=3208,r13;;
            2f6:	30 01 44 20 20 00 	            ld4 r19=[r17]
            2fc:	00 00 04 00       	            nop.i 0x0;;
            300:	0b 90 fc 27 3f 23 	[MMI]       adds r18=-1,r19;;
            306:	00 90 44 20 23 00 	            st4 [r17]=r18
            30c:	00 00 04 00       	            nop.i 0x0;;
            310:	11 00 00 00 01 00 	[MIB]       nop.m 0x0
            316:	00 00 00 02 00 80 	            nop.i 0x0
            31c:	08 00 84 00       	            br.ret.sptk.many b0;;
      
      Much better.
      There is a
            270:	05 40 00 00 00 e1 	[MLX]       mov r8=r0
      which was generated by C code r8 = 0. Below
            2b6:	00 10 81 54 08 00 	            mov.m ar.ccv=r34
      what means that oldval is no longer overwritten.
      
      This is Debian bug#702641
      (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=702641).
      
      The patch is applicable on Kernel 3.9-rc1, 3.2.23 and many other versions.
      Signed-off-by: default avatarStephan Schreiber <info@fs-driver.org>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      b5789c66
    • Steven Rostedt (Red Hat)'s avatar
      tracing: Fix ftrace_dump() · 7462e0e2
      Steven Rostedt (Red Hat) authored
      commit 7fe70b57 upstream.
      
      ftrace_dump() had a lot of issues. What ftrace_dump() does, is when
      ftrace_dump_on_oops is set (via a kernel parameter or sysctl), it
      will dump out the ftrace buffers to the console when either a oops,
      panic, or a sysrq-z occurs.
      
      This was written a long time ago when ftrace was fragile to recursion.
      But it wasn't written well even for that.
      
      There's a possible deadlock that can occur if a ftrace_dump() is happening
      and an NMI triggers another dump. This is because it grabs a lock
      before checking if the dump ran.
      
      It also totally disables ftrace, and tracing for no good reasons.
      
      As the ring_buffer now checks if it is read via a oops or NMI, where
      there's a chance that the buffer gets corrupted, it will disable
      itself. No need to have ftrace_dump() do the same.
      
      ftrace_dump() is now cleaned up where it uses an atomic counter to
      make sure only one dump happens at a time. A simple atomic_inc_return()
      is enough that is needed for both other CPUs and NMIs. No need for
      a spinlock, as if one CPU is running the dump, no other CPU needs
      to do it too.
      
      The tracing_on variable is turned off and not turned on. The original
      code did this, but it wasn't pretty. By just disabling this variable
      we get the result of not seeing traces that happen between crashes.
      
      For sysrq-z, it doesn't get turned on, but the user can always write
      a '1' to the tracing_on file. If they are using sysrq-z, then they should
      know about tracing_on.
      
      The new code is much easier to read and less error prone. No more
      deadlock possibility when an NMI triggers here.
      Reported-by: default avatarzhangwei(Jovi) <jovi.zhangwei@huawei.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      7462e0e2
    • Steven Rostedt (Red Hat)'s avatar
      tracing: Remove most or all of stack tracer stack size from stack_max_size · cde591b5
      Steven Rostedt (Red Hat) authored
      commit 4df29712 upstream.
      
      Currently, the depth reported in the stack tracer stack_trace file
      does not match the stack_max_size file. This is because the stack_max_size
      includes the overhead of stack tracer itself while the depth does not.
      
      The first time a max is triggered, a calculation is not performed that
      figures out the overhead of the stack tracer and subtracts it from
      the stack_max_size variable. The overhead is stored and is subtracted
      from the reported stack size for comparing for a new max.
      
      Now the stack_max_size corresponds to the reported depth:
      
       # cat stack_max_size
      4640
      
       # cat stack_trace
              Depth    Size   Location    (48 entries)
              -----    ----   --------
        0)     4640      32   _raw_spin_lock+0x18/0x24
        1)     4608     112   ____cache_alloc+0xb7/0x22d
        2)     4496      80   kmem_cache_alloc+0x63/0x12f
        3)     4416      16   mempool_alloc_slab+0x15/0x17
      [...]
      
      While testing against and older gcc on x86 that uses mcount instead
      of fentry, I found that pasing in ip + MCOUNT_INSN_SIZE let the
      stack trace show one more function deep which was missing before.
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      cde591b5
    • Steven Rostedt (Red Hat)'s avatar
      tracing: Fix stack tracer with fentry use · 1d2922fe
      Steven Rostedt (Red Hat) authored
      commit d4ecbfc4 upstream.
      
      When gcc 4.6 on x86 is used, the function tracer will use the new
      option -mfentry which does a call to "fentry" at every function
      instead of "mcount". The significance of this is that fentry is
      called as the first operation of the function instead of the mcount
      usage of being called after the stack.
      
      This causes the stack tracer to show some bogus results for the size
      of the last function traced, as well as showing "ftrace_call" instead
      of the function. This is due to the stack frame not being set up
      by the function that is about to be traced.
      
       # cat stack_trace
              Depth    Size   Location    (48 entries)
              -----    ----   --------
        0)     4824     216   ftrace_call+0x5/0x2f
        1)     4608     112   ____cache_alloc+0xb7/0x22d
        2)     4496      80   kmem_cache_alloc+0x63/0x12f
      
      The 216 size for ftrace_call includes both the ftrace_call stack
      (which includes the saving of registers it does), as well as the
      stack size of the parent.
      
      To fix this, if CC_USING_FENTRY is defined, then the stack_tracer
      will reserve the first item in stack_dump_trace[] array when
      calling save_stack_trace(), and it will fill it in with the parent ip.
      Then the code will look for the parent pointer on the stack and
      give the real size of the parent's stack pointer:
      
       # cat stack_trace
              Depth    Size   Location    (14 entries)
              -----    ----   --------
        0)     2640      48   update_group_power+0x26/0x187
        1)     2592     224   update_sd_lb_stats+0x2a5/0x4ac
        2)     2368     160   find_busiest_group+0x31/0x1f1
        3)     2208     256   load_balance+0xd9/0x662
      
      I'm Cc'ing stable, although it's not urgent, as it only shows bogus
      size for item #0, the rest of the trace is legit. It should still be
      corrected in previous stable releases.
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      1d2922fe
    • Steven Rostedt (Red Hat)'s avatar
      tracing: Use stack of calling function for stack tracer · f2547fe3
      Steven Rostedt (Red Hat) authored
      commit 87889501 upstream.
      
      Use the stack of stack_trace_call() instead of check_stack() as
      the test pointer for max stack size. It makes it a bit cleaner
      and a little more accurate.
      
      Adding stable, as a later fix depends on this patch.
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      f2547fe3
    • Zhao Hongjiang's avatar
      aio: fix possible invalid memory access when DEBUG is enabled · bf0f91c0
      Zhao Hongjiang authored
      commit 91d80a84 upstream.
      
      dprintk() shouldn't access @ring after it's unmapped.
      Signed-off-by: default avatarZhao Hongjiang <zhaohongjiang@huawei.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      [bwh: Backported to 3.2: keep the second argument to kunmap_atomic()]
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      bf0f91c0
    • Mathias Krause's avatar
      crypto: algif - suppress sending source address information in recvmsg · 419f4ba0
      Mathias Krause authored
      commit 72a763d8 upstream.
      
      The current code does not set the msg_namelen member to 0 and therefore
      makes net/socket.c leak the local sockaddr_storage variable to userland
      -- 128 bytes of kernel stack memory. Fix that.
      Signed-off-by: default avatarMathias Krause <minipli@googlemail.com>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      419f4ba0
  2. 25 Apr, 2013 30 commits