linux-stable.git/arch/xtensa/kernel, branch v4.9.76

xtensa: don't limit csum_partial export by CONFIG_NET

2017-08-16T20:43:16+00:00

commit 7f81e55c737a8fa82c71f290945d729a4902f8d2 upstream.

csum_partial and csum_partial_copy_generic are defined unconditionally
and are available even when CONFIG_NET is disabled. They are used not
only by the network drivers, but also by scsi and media.
Don't limit these functions export by CONFIG_NET.

Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

mm: larger stack guard gap, between vmas

2017-06-24T05:11:18+00:00

commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream.

Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.

Original-patch-by: Oleg Nesterov 
Original-patch-by: Michal Hocko 
Signed-off-by: Hugh Dickins 
Acked-by: Michal Hocko 
Tested-by: Helge Deller  # parisc
Signed-off-by: Linus Torvalds 
[wt: backport to 4.11: adjust context]
[wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide]
Signed-off-by: Willy Tarreau 
Signed-off-by: Greg Kroah-Hartman

xtensa: don't use linux IRQ #0

2017-06-17T04:41:58+00:00

commit e5c86679d5e864947a52fb31e45a425dea3e7fa9 upstream.

Linux IRQ #0 is reserved for error reporting and may not be used.
Increase NR_IRQS for one additional slot and increase
irq_domain_add_legacy parameter first_irq value to 1, so that linux
IRQ #0 is not associated with hardware IRQ #0 in legacy IRQ domains.
Introduce macro XTENSA_PIC_LINUX_IRQ for static translation of xtensa
PIC hardware IRQ # to linux IRQ #. Use this macro in XTFPGA platform
data definitions.

This fixes inability to use hardware IRQ #0 in configurations that don't
use device tree and allows for non-identity mapping between linux IRQ #
and hardware IRQ #.

Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: move parse_tag_fdt out of #ifdef CONFIG_BLK_DEV_INITRD

2017-03-15T02:02:47+00:00

commit 4ab18701c66552944188dbcd0ce0012729baab84 upstream.

FDT tag parsing is not related to whether BLK_DEV_INITRD is configured
or not, move it out of the corresponding #ifdef/#endif block.
This fixes passing external FDT to the kernel configured w/o
BLK_DEV_INITRD support.

Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: fix noMMU build on cores with MMU

2017-02-09T07:08:25+00:00

commit 4b3e6f2ef3722f1a6a97b6034ed492c1a21fd4ae upstream.

Commit bf15f86b343ed8 ("xtensa: initialize MMU before jumping to reset
vector") calls MMU management functions even when CONFIG_MMU is not
selected. That breaks noMMU build on cores with MMU.

Don't manage MMU when CONFIG_MMU is not selected.

Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: clean up printk usage for boot/crash logging

2016-11-07T07:31:46+00:00

Convert printk(KERN_* to pr_* and printk's without level to pr_cont.
This fixes torn register dumps, stack dumps, stack traces and timestamps
in the middle of 'Calibrating CPU frequency' message.
Also drop unused show_code and drop false comment about show_stack.

Signed-off-by: Max Filippov

Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-10-12T06:38:39+00:00

Pull uaccess.h prepwork from Al Viro:
 "Preparations to tree-wide switch to use of linux/uaccess.h (which,
  obviously, will allow to start unifying stuff for real). The last step
  there, ie

    PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
    sed -i -e "s!$PATT!#include !" \
            `git grep -l "$PATT"|grep -v ^include/linux/uaccess.h`

  is not taken here - I would prefer to do it once just before or just
  after -rc1.  However, everything should be ready for it"

* 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  remove a stray reference to asm/uaccess.h in docs
  sparc64: separate extable_64.h, switch elf_64.h to it
  score: separate extable.h, switch module.h to it
  mips: separate extable.h, switch module.h to it
  x86: separate extable.h, switch sections.h to it
  remove stray include of asm/uaccess.h from cacheflush.h
  mn10300: remove a bogus processor.h->uaccess.h include
  xtensa: split uaccess.h into C and asm sides
  bonding: quit messing with IOCTL
  kill __kernel_ds_p off
  mn10300: finish verify_area() off
  frv: move HAVE_ARCH_UNMAPPED_AREA to pgtable.h
  exceptions: detritus removal

nmi_backtrace: generate one-line reports for idle cpus

2016-10-08T01:46:30+00:00

When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative.  Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".

We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.

This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.

Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf 
Acked-by: Peter Zijlstra (Intel) 
Tested-by: Peter Zijlstra (Intel) 
Tested-by: Daniel Thompson  [arm]
Tested-by: Petr Mladek 
Cc: Aaron Tomlin 
Cc: Peter Zijlstra (Intel) 
Cc: "Rafael J. Wysocki" 
Cc: Russell King 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'xtensa-20161005' of git://github.com/jcmvbkbc/linux-xtensa

2016-10-06T00:44:48+00:00

Pull Xtensa updates from Max Filippov:
 "Updates for the xtensa architecture.  It is a combined set of patches
  for 4.8 that never got to the mainline and new patches for 4.9.

   - add new kernel memory layouts for MMUv3 cores: with 256MB and 512MB
     KSEG size, starting at physical address other than 0

   - make kernel load address configurable

   - clean up kernel memory layout macros

   - drop sysmem early allocator and switch to memblock

   - enable kmemleak and memory reservation from the device tree

   - wire up new syscalls: userfaultfd, membarrier, mlock2,
     copy_file_range, preadv2 and pwritev2

   - add new platform: Cadence Configurable System Platform (CSP) and
     new core variant for it: xt_lnx

   - rearrange CCOUNT calibration code, make most of it generic

   - improve machine reset code (XTFPGA now reboots reliably with MMUv3
     cores)

   - provide default memmap command line option for configurations
     without device tree support

   - ISS fixes: simdisk is now capable of using highmem pages, panic
     correctly terminates simulator"

* tag 'xtensa-20161005' of git://github.com/jcmvbkbc/linux-xtensa: (24 commits)
  xtensa: disable MMU initialization option on MMUv2 cores
  xtensa: add default memmap and mmio32native options to defconfigs
  xtensa: add default memmap option to common_defconfig
  xtensa: add default memmap option to iss_defconfig
  xtensa: ISS: allow simdisk to use high memory buffers
  xtensa: ISS: define simc_exit and use it instead of inline asm
  xtensa: xtfpga: group platform_* functions together
  xtensa: rearrange CCOUNT calibration
  xtensa: xtfpga: use clock provider, don't update DT
  xtensa: Tweak xuartps UART driver Rx watermark for Cadence CSP config.
  xtensa: initialize MMU before jumping to reset vector
  xtensa: fix icountlevel setting in cpu_reset
  xtensa: extract common CPU reset code into separate function
  xtensa: Added Cadence CSP kernel configuration for Xtensa
  xtensa: fix default kernel load address
  xtensa: wire up new syscalls
  xtensa: support reserved-memory DT node
  xtensa: drop sysmem and switch to memblock
  xtensa: minimize use of PLATFORM_DEFAULT_MEM_{ADDR,SIZE}
  xtensa: cleanup MMU setup and kernel layout macros
  ...

xtensa: split uaccess.h into C and asm sides

2016-09-28T01:15:21+00:00

Signed-off-by: Al Viro