linux-stable.git/arch/x86/kernel/check.c, branch linux-4.4.y

x86/corruption-check: Fix panic in memory_corruption_check() when boot option without value is provided

2018-11-21T08:27:30+00:00

commit ccde460b9ae5c2bd5e4742af0a7f623c2daad566 upstream.

memory_corruption_check[{_period|_size}]()'s handlers do not check input
argument before passing it to kstrtoul() or simple_strtoull(). The argument
would be a NULL pointer if each of the kernel parameters, without its
value, is set in command line and thus cause the following panic.

PANIC: early exception 0xe3 IP 10:ffffffff73587c22 error 0 cr2 0x0
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #2
[    0.000000] RIP: 0010:kstrtoull+0x2/0x10
...
[    0.000000] Call Trace
[    0.000000]  ? set_corruption_check+0x21/0x49
[    0.000000]  ? do_early_param+0x4d/0x82
[    0.000000]  ? parse_args+0x212/0x330
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_options+0x20/0x23
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_param+0x2d/0x39
[    0.000000]  ? setup_arch+0x2f7/0xbf4
[    0.000000]  ? start_kernel+0x5e/0x4c2
[    0.000000]  ? load_ucode_bsp+0x113/0x12f
[    0.000000]  ? secondary_startup_64+0xa5/0xb0

This patch adds checks to prevent the panic.

Signed-off-by: He Zhe 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: gregkh@linuxfoundation.org
Cc: kstewart@linuxfoundation.org
Cc: pombredanne@nexb.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1534260823-87917-1-git-send-email-zhe.he@windriver.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'v4.2-rc8' into x86/mm, before applying new changes

2015-08-25T07:59:19+00:00

Signed-off-by: Ingo Molnar

x86/mm: Make kernel/check.c explicitly non-modular

2015-08-25T07:48:38+00:00

The Kconfig currently controlling compilation of this code is:

  arch/x86/Kconfig:config X86_CHECK_BIOS_CORRUPTION
  arch/x86/Kconfig:       bool "Check for low memory corruption"

...meaning that it currently is not being built as a module by
anyone.

Lets remove the couple traces of modularity so that when reading
the code there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the
non-modular case, the init ordering remains unchanged with this
commit.

Signed-off-by: Paul Gortmaker 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1440459295-21814-4-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar

mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute

2015-06-25T00:49:44+00:00

Some high end Intel Xeon systems report uncorrectable memory errors as a
recoverable machine check.  Linux has included code for some time to
process these and just signal the affected processes (or even recover
completely if the error was in a read only page that can be replaced by
reading from disk).

But we have no recovery path for errors encountered during kernel code
execution.  Except for some very specific cases were are unlikely to ever
be able to recover.

Enter memory mirroring. Actually 3rd generation of memory mirroing.

Gen1: All memory is mirrored
	Pro: No s/w enabling - h/w just gets good data from other side of the
	     mirror
	Con: Halves effective memory capacity available to OS/applications

Gen2: Partial memory mirror - just mirror memory begind some memory controllers
	Pro: Keep more of the capacity
	Con: Nightmare to enable. Have to choose between allocating from
	     mirrored memory for safety vs. NUMA local memory for performance

Gen3: Address range partial memory mirror - some mirror on each memory
      controller
	Pro: Can tune the amount of mirror and keep NUMA performance
	Con: I have to write memory management code to implement

The current plan is just to use mirrored memory for kernel allocations.
This has been broken into two phases:

1) This patch series - find the mirrored memory, use it for boot time
   allocations

2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the
   unused mirrored memory from mm/memblock.c and only give it out to
   select kernel allocations (this is still being scoped because
   page_alloc.c is scary).

This patch (of 3):

Add extra "flags" to memblock to allow selection of memory based on
attribute.  No functional changes

Signed-off-by: Tony Luck 
Cc: Xishi Qiu 
Cc: Hanjun Guo 
Cc: Xiexiuqi 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: Yinghai Lu 
Cc: Naoya Horiguchi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86/mm: memblock: switch to use NUMA_NO_NODE

2014-01-22T00:19:47+00:00

Update X86 code to use NUMA_NO_NODE instead of MAX_NUMNODES while
calling memblock APIs, because memblock API will be changed to use
NUMA_NO_NODE and will produce warning during boot otherwise.

See:
 https://lkml.org/lkml/2013/12/9/898

Signed-off-by: Grygorii Strashko 
Cc: Santosh Shilimkar 
Cc: Stephen Rothwell 
Cc: Tejun Heo 
Cc: Yinghai Lu 
Acked-by: David Rientjes 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86: kernel/check.c simple_strtoul cleanup

2012-05-15T22:36:41+00:00

Change set_corruption_check() and set_corruption_check_period()
in kernel/check.c to call kstrtoul() instead of calling
obsoleted simple_strtoul().

Signed-off-by: Shuah Khan 
Link: http://lkml.kernel.org/r/1336326908.2897.12.camel@lorien2
Signed-off-by: H. Peter Anvin

memblock, x86: Replace memblock_x86_reserve/free_range() with generic ones

2011-07-14T18:47:53+00:00

Other than sanity check and debug message, the x86 specific version of
memblock reserve/free functions are simple wrappers around the generic
versions - memblock_reserve/free().

This patch adds debug messages with caller identification to the
generic versions and replaces x86 specific ones and kills them.
arch/x86/include/asm/memblock.h and arch/x86/mm/memblock.c are empty
after this change and removed.

Signed-off-by: Tejun Heo 
Link: http://lkml.kernel.org/r/1310462166-31469-14-git-send-email-tj@kernel.org
Cc: Yinghai Lu 
Cc: Benjamin Herrenschmidt 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Signed-off-by: H. Peter Anvin

x86: Replace memblock_x86_find_in_range_size() with for_each_free_mem_range()

2011-07-14T18:47:48+00:00

setup_bios_corruption_check() and memtest do_one_pass() open code
memblock free area iteration using memblock_x86_find_in_range_size().
Convert them to use for_each_free_mem_range() instead.

This leaves memblock_x86_find_in_range_size() and
memblock_x86_check_reserved_size() unused.  Kill them.

Signed-off-by: Tejun Heo 
Link: http://lkml.kernel.org/r/1310462166-31469-8-git-send-email-tj@kernel.org
Cc: Yinghai Lu 
Cc: Benjamin Herrenschmidt 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Signed-off-by: H. Peter Anvin

memblock: Kill MEMBLOCK_ERROR

2011-07-13T23:36:01+00:00

25818f0f28 (memblock: Make MEMBLOCK_ERROR be 0) thankfully made
MEMBLOCK_ERROR 0 and there already are codes which expect error return
to be 0.  There's no point in keeping MEMBLOCK_ERROR around.  End its
misery.

Signed-off-by: Tejun Heo 
Link: http://lkml.kernel.org/r/1310457490-3356-6-git-send-email-tj@kernel.org
Cc: Yinghai Lu 
Cc: Benjamin Herrenschmidt 
Signed-off-by: H. Peter Anvin

x86: Don't check for BIOS corruption in first 64K when there's no need to

2011-03-09T15:36:41+00:00

Due to commit 781c5a67f152c17c3e4a9ed9647f8c0be6ea5ae9 it is
likely that the number of areas to scan for BIOS corruption is 0
 -- especially when the first 64K is already reserved
(X86_RESERVE_LOW is 64K by default).

If that's the case then don't set up the scan.

Signed-off-by: Naga Chumbalkar 
Cc: 
LKML-Reference: <20110225202838.2229.71011.sendpatchset@nchumbalkar.americas.hpqcorp.net>
Signed-off-by: Ingo Molnar