linux-toradex.git/arch, branch v4.7-rc2

parisc: Move die_if_kernel() prototype into traps.h header

2016-06-05T06:49:01+00:00

Signed-off-by: Helge Deller

parisc: Fix pagefault crash in unaligned __get_user() call

2016-06-05T06:48:24+00:00

One of the debian buildd servers had this crash in the syslog without
any other information:

 Unaligned handler failed, ret = -2
 clock_adjtime (pid 22578): Unaligned data reference (code 28)
 CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G  E  4.5.0-2-parisc64-smp #1 Debian 4.5.4-1
 task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000

      YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
 PSW: 00001000000001001111100000001111 Tainted: G            E
 r00-03  000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0
 r04-07  00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff
 r08-11  0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4
 r12-15  000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b
 r16-19  0000000000028800 0000000000000001 0000000000000070 00000001bde7c218
 r20-23  0000000000000000 00000001bde7c210 0000000000000002 0000000000000000
 r24-27  0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0
 r28-31  0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218
 sr00-03  0000000001200000 0000000001200000 0000000000000000 0000000001200000
 sr04-07  0000000000000000 0000000000000000 0000000000000000 0000000000000000

 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88
  IIR: 0ca0d089    ISR: 0000000001200000  IOR: 00000000fa6f7fff
  CPU:        1   CR30: 00000001bde7c000 CR31: ffffffffffffffff
  ORIG_R28: 00000002369fe628
  IAOQ[0]: compat_get_timex+0x2dc/0x3c0
  IAOQ[1]: compat_get_timex+0x2e0/0x3c0
  RP(r2): compat_get_timex+0x40/0x3c0
 Backtrace:
  [<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0
  [<0000000040205024>] syscall_exit+0x0/0x14

This means the userspace program clock_adjtime called the clock_adjtime()
syscall and then crashed inside the compat_get_timex() function.
Syscalls should never crash programs, but instead return EFAULT.

The IIR register contains the executed instruction, which disassebles
into "ldw 0(sr3,r5),r9".
This load-word instruction is part of __get_user() which tried to read the word
at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in.  The
unaligned handler is able to emulate all ldw instructions, but it fails if it
fails to read the source e.g. because of page fault.

The following program reproduces the problem:

#define _GNU_SOURCE
#include 
#include 
#include 

int main(void) {
        /* allocate 8k */
        char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
        /* free second half (upper 4k) and make it invalid. */
        munmap(ptr+4096, 4096);
        /* syscall where first int is unaligned and clobbers into invalid memory region */
        /* syscall should return EFAULT */
        return syscall(__NR_clock_adjtime, 0, ptr+4095);
}

To fix this issue we simply need to check if the faulting instruction address
is in the exception fixup table when the unaligned handler failed. If it
is, call the fixup routine instead of crashing.

While looking at the unaligned handler I found another issue as well: The
target register should not be modified if the handler was unsuccessful.

Signed-off-by: Helge Deller 
Cc: stable@vger.kernel.org

parisc: Fix printk time during boot

2016-06-05T06:45:09+00:00

Avoid showing invalid printk time stamps during boot.

Signed-off-by: Helge Deller 
Reviewed-by: Aaro Koskinen

parisc: Fix backtrace on PA-RISC

2016-06-04T20:05:07+00:00

This patch fixes backtrace on PA-RISC

There were several problems:

1) The code that decodes instructions handles instructions that subtract
from the stack pointer incorrectly. If the instruction subtracts the
number X from the stack pointer the code increases the frame size by
(0x100000000-X).  This results in invalid accesses to memory and
recursive page faults.

2) Because gcc reorders blocks, handling instructions that subtract from
the frame pointer is incorrect. For example, this function
	int f(int a)
	{
		if (__builtin_expect(a, 1))
			return a;
		g();
		return a;
	}
is compiled in such a way, that the code that decreases the stack
pointer for the first "return a" is placed before the code for "g" call.
If we recognize this decrement, we mistakenly believe that the frame
size for the "g" call is zero.

To fix problems 1) and 2), the patch doesn't recognize instructions that
decrease the stack pointer at all. To further safeguard the unwind code
against nonsense values, we don't allow frame size larger than
Total_frame_size.

3) The backtrace is not locked. If stack dump races with module unload,
invalid table can be accessed.

This patch adds a spinlock when processing module tables.

Note, that for correct backtrace, you need recent binutils.
Binutils 2.18 from Debian 5 produce garbage unwind tables.
Binutils 2.21 work better (it sometimes forgets function frames, but at
least it doesn't generate garbage).

Signed-off-by: Mikulas Patocka 
Signed-off-by: Helge Deller

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

2016-06-03T23:12:35+00:00

Pull irq fixes from Thomas Gleixner:
 - a few simple fixes for fallout from the recent gic-v3 changes
 - a workaround for a Cavium thunderX erratum
 - a bugfix for the pic32 irqchip to make external interrupts work proper
 - a missing return value in the generic IPI management code

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/irq-pic32-evic: Fix bug with external interrupts.
  irqchip/gicv3-its: numa: Enable workaround for Cavium thunderx erratum 23144
  irqchip/gic-v3: Fix quiescence check in gic_enable_redist
  irqchip/gic-v3: Fix copy+paste mistakes in defines
  irqchip/gic-v3: Fix ICC_SGI1R_EL1.INTID decoding mask
  genirq: Fix missing return value in irq_destroy_ipi()

Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm

2016-06-03T21:39:29+00:00

Pull ARM fix from Russell King:
 "Just one fix to the ptrace code, spotted by Simon Marchi, where if a
  thread migrates to a different CPU and the VFP registers are changed
  through ptrace, the application doesn't see the updated VFP registers"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: fix PTRACE_SETVFPREGS on SMP systems

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2016-06-03T21:29:47+00:00

Pull arm64 fixes from Will Deacon:
 "The main thing here is reviving hugetlb support using contiguous ptes,
  which we ended up reverting at the last minute in 4.5 pending a fix
  which went into the core mm/ code during the recent merge window.

   - Revert a previous revert and get hugetlb going with contiguous hints
   - Wire up missing compat syscalls
   - Enable CONFIG_SET_MODULE_RONX by default
   - Add missing line to our compat /proc/cpuinfo output
   - Clarify levels in our page table dumps
   - Fix booting with RANDOMIZE_TEXT_OFFSET enabled
   - Misc fixes to the ARM CPU PMU driver (refcounting, probe failure)
   - Remove some dead code and update a comment"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fix alignment when RANDOMIZE_TEXT_OFFSET is enabled
  arm64: move {PAGE,CONT}_SHIFT into Kconfig
  arm64: mm: dump: log span level
  arm64: update stale PAGE_OFFSET comment
  drivers/perf: arm_pmu: Avoid leaking pmu->irq_affinity on error
  drivers/perf: arm_pmu: Defer the setting of __oprofile_cpu_pmu
  drivers/perf: arm_pmu: Fix reference count of a device_node in of_pmu_irq_cfg
  arm64: report CPU number in bad_mode
  arm64: unistd32.h: wire up missing syscalls for compat tasks
  arm64: Provide "model name" in /proc/cpuinfo for PER_LINUX32 tasks
  arm64: enable CONFIG_SET_MODULE_RONX by default
  arm64: Remove orphaned __addr_ok() definition
  Revert "arm64: hugetlb: partial revert of 66b3923a1a0f"

Merge tag 'powerpc-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2016-06-03T21:20:22+00:00

Pull powerpc fixes from Michael Ellerman:
 - Handle RTAS delay requests in configure_bridge from Russell Currey
 - Refactor the configure_bridge RTAS tokens from Russell Currey
 - Fix definition of SIAR and SDAR registers from Thomas Huth
 - Use privileged SPR number for MMCR2 from Thomas Huth
 - Update LPCR only if it is powernv from Aneesh Kumar K.V
 - Fix the reference bit update when handling hash fault from Aneesh
   Kumar K.V
 - Add missing tlb flush from Aneesh Kumar K.V
 - Add POWER8NVL support to ibm,client-architecture-support call from
   Thomas Huth

* tag 'powerpc-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call
  powerpc/mm/radix: Add missing tlb flush
  powerpc/mm/hash: Fix the reference bit update when handling hash fault
  powerpc/mm/radix: Update LPCR only if it is powernv
  powerpc: Use privileged SPR number for MMCR2
  powerpc: Fix definition of SIAR and SDAR registers
  powerpc/pseries/eeh: Refactor the configure_bridge RTAS tokens
  powerpc/pseries/eeh: Handle RTAS delay requests in configure_bridge

arm64: fix alignment when RANDOMIZE_TEXT_OFFSET is enabled

2016-06-03T09:57:18+00:00

With ARM64_64K_PAGES and RANDOMIZE_TEXT_OFFSET enabled, we hit the
following issue on the boot:

kernel BUG at arch/arm64/mm/mmu.c:480!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 4.6.0 #310
Hardware name: ARM Juno development board (r2) (DT)
task: ffff000008d58a80 ti: ffff000008d30000 task.ti: ffff000008d30000
PC is at map_kernel_segment+0x44/0xb0
LR is at paging_init+0x84/0x5b0
pc : [] lr : [] pstate: 600002c5

Call trace:
[] map_kernel_segment+0x44/0xb0
[] paging_init+0x84/0x5b0
[] setup_arch+0x198/0x534
[] start_kernel+0x70/0x388
[] __primary_switched+0x30/0x74

Commit 7eb90f2ff7e3 ("arm64: cover the .head.text section in the .text
segment mapping") removed the alignment between the .head.text and .text
sections, and used the _text rather than the _stext interval for mapping
the .text segment.

Prior to this commit _stext was always section aligned and didn't cause
any issue even when RANDOMIZE_TEXT_OFFSET was enabled. Since that
alignment has been removed and _text is used to map the .text segment,
we need ensure _text is always page aligned when RANDOMIZE_TEXT_OFFSET
is enabled.

This patch adds logic to TEXT_OFFSET fuzzing to ensure that the offset
is always aligned to the kernel page size. To ensure this, we rely on
the PAGE_SHIFT being available via Kconfig.

Signed-off-by: Mark Rutland 
Reported-by: Sudeep Holla 
Cc: Ard Biesheuvel 
Cc: Catalin Marinas 
Cc: Will Deacon 
Fixes: 7eb90f2ff7e3 ("arm64: cover the .head.text section in the .text segment mapping")
Signed-off-by: Will Deacon

arm64: move {PAGE,CONT}_SHIFT into Kconfig

2016-06-03T09:57:18+00:00

In some cases (e.g. the awk for CONFIG_RANDOMIZE_TEXT_OFFSET) we would
like to make use of PAGE_SHIFT outside of code that can include the
usual header files.

Add a new CONFIG_ARM64_PAGE_SHIFT for this, likewise with
ARM64_CONT_SHIFT for consistency.

Signed-off-by: Mark Rutland 
Cc: Ard Biesheuvel 
Cc: Catalin Marinas 
Cc: Sudeep Holla 
Cc: Will Deacon 
Signed-off-by: Will Deacon