13 Sep, 2013
2 commits
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Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.Signed-off-by: Johannes Weiner
Reviewed-by: Michal Hocko
Cc: David Rientjes
Cc: KAMEZAWA Hiroyuki
Cc: azurIt
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Kernel faults are expected to handle OOM conditions gracefully (gup,
uaccess etc.), so they should never invoke the OOM killer. Reserve this
for faults triggered in user context when it is the only option.Most architectures already do this, fix up the remaining few.
Signed-off-by: Johannes Weiner
Reviewed-by: Michal Hocko
Acked-by: KOSAKI Motohiro
Cc: David Rientjes
Cc: KAMEZAWA Hiroyuki
Cc: azurIt
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Sep, 2013
2 commits
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These handlers are not optional and need in our case
dummy implementions to avoid NULL pointer bugs within
the irq core code.Reported-and-tested-by: Toralf Foester
Signed-off-by: Richard Weinberger -
UML needs it's own probe_kernel_read() to handle kernel
mode faults correctly.
The implementation uses mincore() on the host side to detect
whether a page is owned by the UML kernel process.This fixes also a possible crash when sysrq-t is used.
Starting with 3.10 sysrq-t calls probe_kernel_read() to
read details from the kernel workers. As kernel worker are
completely async pointers may turn NULL while reading them.Cc:
Cc:
Cc: # 3.10.x
Signed-off-by: Richard Weinberger
19 Jul, 2013
3 commits
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Currently we use both struct siginfo and siginfo_t.
Let's use struct siginfo internally to avoid ongoing
compiler warning. We are allowed to do so because
struct siginfo and siginfo_t are equivalent.Signed-off-by: Richard Weinberger
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Ensure that a process cannot destroy his stub pages with
using MADV_DONTNEED and friends.Reported-by: toralf.foerster@gmx.de
Signed-off-by: Richard Weinberger -
In case of an error it must not return -EFAULT.
Return 0 like all other archs do.Reported-by: toralf.foerster@gmx.de
Signed-off-by: Richard Weinberger
04 Jul, 2013
5 commits
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Prepare for removing num_physpages and simplify mem_init().
Signed-off-by: Jiang Liu
Cc: Jeff Dike
Cc: Richard Weinberger
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Normalize global variables exported by vmlinux.lds to conform usage
guidelines from include/asm-generic/sections.h.1) Use _text to mark the start of the kernel image including the head
text, and _stext to mark the start of the .text section.
2) Export mandatory global variables __bss_stop.
3) Adjust __init_begin and __init_end to avoid acrossing .text and
.data sections.Signed-off-by: Jiang Liu
Cc: Jeff Dike
Cc: Richard Weinberger
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Concentrate code to modify totalram_pages into the mm core, so the arch
memory initialized code doesn't need to take care of it. With these
changes applied, only following functions from mm core modify global
variable totalram_pages: free_bootmem_late(), free_all_bootmem(),
free_all_bootmem_node(), adjust_managed_page_count().With this patch applied, it will be much more easier for us to keep
totalram_pages and zone->managed_pages in consistence.Signed-off-by: Jiang Liu
Acked-by: David Howells
Cc: "H. Peter Anvin"
Cc: "Michael S. Tsirkin"
Cc:
Cc: Arnd Bergmann
Cc: Catalin Marinas
Cc: Chris Metcalf
Cc: Geert Uytterhoeven
Cc: Ingo Molnar
Cc: Jeremy Fitzhardinge
Cc: Jianguo Wu
Cc: Joonsoo Kim
Cc: Kamezawa Hiroyuki
Cc: Konrad Rzeszutek Wilk
Cc: Marek Szyprowski
Cc: Mel Gorman
Cc: Michel Lespinasse
Cc: Minchan Kim
Cc: Rik van Riel
Cc: Rusty Russell
Cc: Tang Chen
Cc: Tejun Heo
Cc: Thomas Gleixner
Cc: Wen Congyang
Cc: Will Deacon
Cc: Yasuaki Ishimatsu
Cc: Yinghai Lu
Cc: Russell King
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Address more review comments from last round of code review.
1) Enhance free_reserved_area() to support poisoning freed memory with
pattern '0'. This could be used to get rid of poison_init_mem()
on ARM64.
2) A previous patch has disabled memory poison for initmem on s390
by mistake, so restore to the original behavior.
3) Remove redundant PAGE_ALIGN() when calling free_reserved_area().Signed-off-by: Jiang Liu
Cc: Geert Uytterhoeven
Cc: "H. Peter Anvin"
Cc: "Michael S. Tsirkin"
Cc:
Cc: Arnd Bergmann
Cc: Catalin Marinas
Cc: Chris Metcalf
Cc: David Howells
Cc: Ingo Molnar
Cc: Jeremy Fitzhardinge
Cc: Jianguo Wu
Cc: Joonsoo Kim
Cc: Kamezawa Hiroyuki
Cc: Konrad Rzeszutek Wilk
Cc: Marek Szyprowski
Cc: Mel Gorman
Cc: Michel Lespinasse
Cc: Minchan Kim
Cc: Rik van Riel
Cc: Rusty Russell
Cc: Tang Chen
Cc: Tejun Heo
Cc: Thomas Gleixner
Cc: Wen Congyang
Cc: Will Deacon
Cc: Yasuaki Ishimatsu
Cc: Yinghai Lu
Cc: Russell King
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Change signature of free_reserved_area() according to Russell King's
suggestion to fix following build warnings:arch/arm/mm/init.c: In function 'mem_init':
arch/arm/mm/init.c:603:2: warning: passing argument 1 of 'free_reserved_area' makes integer from pointer without a cast [enabled by default]
free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, 0, NULL);
^
In file included from include/linux/mman.h:4:0,
from arch/arm/mm/init.c:15:
include/linux/mm.h:1301:22: note: expected 'long unsigned int' but argument is of type 'void *'
extern unsigned long free_reserved_area(unsigned long start, unsigned long end,mm/page_alloc.c: In function 'free_reserved_area':
>> mm/page_alloc.c:5134:3: warning: passing argument 1 of 'virt_to_phys' makes pointer from integer without a cast [enabled by default]
In file included from arch/mips/include/asm/page.h:49:0,
from include/linux/mmzone.h:20,
from include/linux/gfp.h:4,
from include/linux/mm.h:8,
from mm/page_alloc.c:18:
arch/mips/include/asm/io.h:119:29: note: expected 'const volatile void *' but argument is of type 'long unsigned int'
mm/page_alloc.c: In function 'free_area_init_nodes':
mm/page_alloc.c:5030:34: warning: array subscript is below array bounds [-Warray-bounds]Also address some minor code review comments.
Signed-off-by: Jiang Liu
Reported-by: Arnd Bergmann
Cc: "H. Peter Anvin"
Cc: "Michael S. Tsirkin"
Cc:
Cc: Catalin Marinas
Cc: Chris Metcalf
Cc: David Howells
Cc: Geert Uytterhoeven
Cc: Ingo Molnar
Cc: Jeremy Fitzhardinge
Cc: Jianguo Wu
Cc: Joonsoo Kim
Cc: Kamezawa Hiroyuki
Cc: Konrad Rzeszutek Wilk
Cc: Marek Szyprowski
Cc: Mel Gorman
Cc: Michel Lespinasse
Cc: Minchan Kim
Cc: Rik van Riel
Cc: Rusty Russell
Cc: Tang Chen
Cc: Tejun Heo
Cc: Thomas Gleixner
Cc: Wen Congyang
Cc: Will Deacon
Cc: Yasuaki Ishimatsu
Cc: Yinghai Lu
Cc: Russell King
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
19 Jun, 2013
1 commit
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Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time
back and the comments/Documentation never got updated.I figured it out when I was going through sched-domains.txt and so thought of
fixing it globally.I haven't crossed check if the stuff that is referenced in sched/core.c by all
these files is still present and hasn't changed as that wasn't the motive behind
this patch.Signed-off-by: Viresh Kumar
Signed-off-by: Peter Zijlstra
Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar
01 May, 2013
1 commit
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Both dump_stack() and show_stack() are currently implemented by each
architecture. show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack(). On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().There's no reason to require archs to implement two separate but mostly
identical functions. It leads to unnecessary subtle information.This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin. Blackfin's
dump_stack() does something wonky that I don't understand.Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information. This is used
in blackfin.This patch brings the following behavior changes.
* On some archs, an extra level in backtrace for show_stack() could be
printed. This is because the top frame was determined in
dump_stack() on those archs while generic dump_stack() can't do that
reliably. It can be compensated by inlining dump_stack() but not
sure whether that'd be necessary.* Most archs didn't use to print debug info on dump_stack(). They do
now.An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Hardware name: empty
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[] dump_stack+0x19/0x1b
[] warn_slowpath_common+0x7f/0xc0
[] warn_slowpath_null+0x1a/0x20
[] init_workqueues+0x35/0x505
...v2: CPU number added to the generic debug info as requested by s390
folks and dropped the s390 specific dump_stack(). This loses %ksp
from the debug message which the maintainers think isn't important
enough to keep the s390-specific dump_stack() implementation.dump_stack_print_info() is moved to kernel/printk.c from
lib/dump_stack.c. Because linkage is per objecct file,
dump_stack_print_info() living in the same lib file as generic
dump_stack() means that archs which implement custom dump_stack()
- at this point, only blackfin - can't use dump_stack_print_info()
as that will bring in the generic version of dump_stack() too. v1
The v1 patch broke build on blackfin due to this issue. The build
breakage was reported by Fengguang Wu.Signed-off-by: Tejun Heo
Acked-by: David S. Miller
Acked-by: Vineet Gupta
Acked-by: Jesper Nilsson
Acked-by: Vineet Gupta
Acked-by: Martin Schwidefsky [s390 bits]
Cc: Heiko Carstens
Cc: Mike Frysinger
Cc: Fengguang Wu
Cc: Bjorn Helgaas
Cc: Sam Ravnborg
Acked-by: Richard Kuo [hexagon bits]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Apr, 2013
4 commits
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Pull SMP/hotplug changes from Ingo Molnar:
"This is a pretty large, multi-arch series unifying and generalizing
the various disjunct pieces of idle routines that architectures have
historically copied from each other and have grown in random, wildly
inconsistent and sometimes buggy directions:101 files changed, 455 insertions(+), 1328 deletions(-)
this went through a number of review and test iterations before it was
committed, it was tested on various architectures, was exposed to
linux-next for quite some time - nevertheless it might cause problems
on architectures that don't read the mailing lists and don't regularly
test linux-next.This cat herding excercise was motivated by the -rt kernel, and was
brought to you by Thomas "the Whip" Gleixner."* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
idle: Remove GENERIC_IDLE_LOOP config switch
um: Use generic idle loop
ia64: Make sure interrupts enabled when we "safe_halt()"
sparc: Use generic idle loop
idle: Remove unused ARCH_HAS_DEFAULT_IDLE
bfin: Fix typo in arch_cpu_idle()
xtensa: Use generic idle loop
x86: Use generic idle loop
unicore: Use generic idle loop
tile: Use generic idle loop
tile: Enter idle with preemption disabled
sh: Use generic idle loop
score: Use generic idle loop
s390: Use generic idle loop
powerpc: Use generic idle loop
parisc: Use generic idle loop
openrisc: Use generic idle loop
mn10300: Use generic idle loop
mips: Use generic idle loop
microblaze: Use generic idle loop
... -
The early console implementations are the same all over the place. Move
the print function to kernel/printk and get rid of the copies.[akpm@linux-foundation.org: arch/mips/kernel/early_printk.c needs kernel.h for va_list]
[paul.gortmaker@windriver.com: sh4: make the bios early console support depend on EARLY_PRINTK]
Signed-off-by: Thomas Gleixner
Signed-off-by: Paul Gortmaker
Cc: Russell King
Acked-by: Mike Frysinger
Cc: Michal Simek
Cc: Ralf Baechle
Cc: Benjamin Herrenschmidt
Cc: Paul Mundt
Cc: "David S. Miller"
Cc: Chris Metcalf
Cc: Richard Weinberger
Reviewed-by: Ingo Molnar
Tested-by: Paul Gortmaker
Cc: Geert Uytterhoeven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Use helper function free_highmem_page() to free highmem pages into
the buddy system.Signed-off-by: Jiang Liu
Cc: Jeff Dike
Cc: Richard Weinberger
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Use common help functions to free reserved pages.
Signed-off-by: Jiang Liu
Cc: Jeff Dike
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Apr, 2013
1 commit
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Signed-off-by: Richard Weinberger
Cc: user-mode-linux-devel@lists.sourceforge.net
Link: http://lkml.kernel.org/r/1366149209-24787-1-git-send-email-richard@nod.at
Signed-off-by: Thomas Gleixner
04 Feb, 2013
1 commit
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Signed-off-by: Al Viro
20 Dec, 2012
1 commit
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Conditional on CONFIG_GENERIC_SIGALTSTACK; architectures that do not
select it are completely unaffectedSigned-off-by: Al Viro
29 Nov, 2012
5 commits
-
Signed-off-by: Al Viro
-
Signed-off-by: Al Viro
-
Signed-off-by: Al Viro
-
copy_thread() on um will do the right thing when getting 0 for sp...
Signed-off-by: Al Viro
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... or we'll end up buggering the results of ELF_PLAT_INIT()
Signed-off-by: Al Viro
13 Oct, 2012
2 commits
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Pull third pile of kernel_execve() patches from Al Viro:
"The last bits of infrastructure for kernel_thread() et.al., with
alpha/arm/x86 use of those. Plus sanitizing the asm glue and
do_notify_resume() on alpha, fixing the "disabled irq while running
task_work stuff" breakage there.At that point the rest of kernel_thread/kernel_execve/sys_execve work
can be done independently for different architectures. The only
pending bits that do depend on having all architectures converted are
restrictred to fs/* and kernel/* - that'll obviously have to wait for
the next cycle.I thought we'd have to wait for all of them done before we start
eliminating the longjump-style insanity in kernel_execve(), but it
turned out there's a very simple way to do that without flagday-style
changes."* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
alpha: switch to saner kernel_execve() semantics
arm: switch to saner kernel_execve() semantics
x86, um: convert to saner kernel_execve() semantics
infrastructure for saner ret_from_kernel_thread semantics
make sure that kernel_thread() callbacks call do_exit() themselves
make sure that we always have a return path from kernel_execve()
ppc: eeh_event should just use kthread_run()
don't bother with kernel_thread/kernel_execve for launching linuxrc
alpha: get rid of switch_stack argument of do_work_pending()
alpha: don't bother passing switch_stack separately from regs
alpha: take SIGPENDING/NOTIFY_RESUME loop into signal.c
alpha: simplify TIF_NEED_RESCHED handling -
Signed-off-by: Al Viro
10 Oct, 2012
4 commits
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Pull generic execve() changes from Al Viro:
"This introduces the generic kernel_thread() and kernel_execve()
functions, and switches x86, arm, alpha, um and s390 over to them."* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits)
s390: convert to generic kernel_execve()
s390: switch to generic kernel_thread()
s390: fold kernel_thread_helper() into ret_from_fork()
s390: fold execve_tail() into start_thread(), convert to generic sys_execve()
um: switch to generic kernel_thread()
x86, um/x86: switch to generic sys_execve and kernel_execve
x86: split ret_from_fork
alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
alpha: switch to generic kernel_thread()
alpha: switch to generic sys_execve()
arm: get rid of execve wrapper, switch to generic execve() implementation
arm: optimized current_pt_regs()
arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk]
generic sys_execve()
generic kernel_execve()
new helper: current_pt_regs()
preparation for generic kernel_thread()
um: kill thread->forking
um: let signal_delivered() do SIGTRAP on singlestepping into handler
... -
Pull UML changes from Richard Weinberger:
"UML receives this time only cleanups.The most outstanding change is the 'include "foo.h"' do 'include
' conversion done by Al Viro.It touches many files, that's why the diffstat is rather big."
* 'for-linus-37rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
typo in UserModeLinux-HOWTO
hppfs: fix the return value of get_inode()
hostfs: drop vmtruncate
um: get rid of pointless include "..." where include will do
um: move sysrq.h out of include/shared
um/x86: merge 32 and 64 bit variants of ptrace.h
um/x86: merge 32 and 64bit variants of checksum.h -
Signed-off-by: Al Viro
Signed-off-by: Richard Weinberger -
never used by userland-side objects
Signed-off-by: Al Viro
Signed-off-by: Richard Weinberger
09 Oct, 2012
1 commit
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.fault now can retry. The retry can break state machine of .fault. In
filemap_fault, if page is miss, ra->mmap_miss is increased. In the second
try, since the page is in page cache now, ra->mmap_miss is decreased. And
these are done in one fault, so we can't detect random mmap file access.Add a new flag to indicate .fault is tried once. In the second try, skip
ra->mmap_miss decreasing. The filemap_fault state machine is ok with it.I only tested x86, didn't test other archs, but looks the change for other
archs is obvious, but who knows :)Signed-off-by: Shaohua Li
Cc: Rik van Riel
Cc: Wu Fengguang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 Oct, 2012
2 commits
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Signed-off-by: Al Viro
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32bit wrapper is lost on that; 64bit one is *not*, since
we need to arrange for full pt_regs on stack when we call
sys_execve() and we need to load callee-saved ones from
there afterwards.Signed-off-by: Al Viro
28 Sep, 2012
4 commits
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we only use that to tell copy_thread() done by syscall from that
done by kernel_thread(). However, it's easier to do simply by
checking PF_KTHREAD in thread flags.Merge sys_clone() guts for 32bit and 64bit, while we are at it...
Signed-off-by: Al Viro
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... rather than duplicating that in sigframe setup code (and doing that
inconsistently, at that)Signed-off-by: Al Viro
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Signed-off-by: Al Viro
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... assuming it's needed to be done at all
Signed-off-by: Al Viro
20 Sep, 2012
1 commit
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we only use that to tell copy_thread() done by syscall from that
done by kernel_thread(). However, it's easier to do simply by
checking PF_KTHREAD in thread flags.Merge sys_clone() guts for 32bit and 64bit, while we are at it...
Signed-off-by: Al Viro