01 Feb, 2017
1 commit
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commit 2ad5d52d42810bed95100a3d912679d8864421ec upstream.
In swab.h the "#if BITS_PER_LONG > 32" breaks compiling userspace programs if
BITS_PER_LONG is #defined by userspace with the sizeof() compiler builtin.Solve this problem by using __BITS_PER_LONG instead. Since we now
#include asm/bitsperlong.h avoid further potential userspace pollution
by moving the #define of SHIFT_PER_LONG to bitops.h which is not
exported to userspace.This patch unbreaks compiling qemu on hppa/parisc.
Signed-off-by: Helge Deller
Signed-off-by: Greg Kroah-Hartman
12 Jan, 2017
2 commits
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commit 41744213602a206f24adcb4a2b7551db3c700e72 upstream.
The cr16 interval timer of each CPU is not syncronized to other cr16
timers in other CPUs in a SMP system. So, delay the registration of the
cr16 clocksource until all CPUs have been detected and then - if we are
on a SMP machine - mark the cr16 clocksource as unstable and lower it's
rating before registering it at the clocksource framework.This patch fixes the stalled CPU warnings which we have seen since
introduction of the cr16 clocksource.Signed-off-by: Helge Deller
Signed-off-by: Greg Kroah-Hartman -
commit b4a9eb4cd5966c8aad3d007d206a2cbda97d6928 upstream.
Add a leading line break else printed line gets too long.
Signed-off-by: Helge Deller
Signed-off-by: Greg Kroah-Hartman
09 Dec, 2016
1 commit
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At bootup we run measurements to calculate the best threshold for when we
should be using full TLB flushes instead of just flushing a specific amount of
TLB entries. This performance test is run over the kernel text segment.But running this TLB performance test on the kernel text segment turned out to
crash some SMP machines when the kernel text pages were mapped as huge pages.To avoid those crashes this patch simply skips this test on some SMP machines
and calculates an optimal threshold based on the maximum number of available
TLB entries and number of online CPUs.On a technical side, this seems to happen:
The TLB measurement code uses flush_tlb_kernel_range() to flush specific TLB
entries with a page size of 4k (pdtlb 0(sr1,addr)). On UP systems this purge
instruction seems to work without problems even if the pages were mapped as
huge pages. But on SMP systems the TLB purge instruction is broadcasted to
other CPUs. Those CPUs then crash the machine because the page size is not as
expected. C8000 machines with PA8800/PA8900 CPUs were not affected by this
problem, because the required cache coherency prohibits to use huge pages at
all. Sadly I didn't found any documentation about this behaviour, so this
finding is purely based on testing with phyiscal SMP machines (A500-44 and
J5000, both were 2-way boxes).Cc: # v3.18+
Signed-off-by: Helge Deller
07 Dec, 2016
2 commits
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We have four routines in pacache.S that use temporary alias pages:
copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and
flush_icache_page_asm(). copy_user_page_asm() and clear_user_page_asm()
don't purge the TLB entry used for the operation.
flush_dcache_page_asm() and flush_icache_page_asm do purge the entry.Presumably, this was thought to optimize TLB use. However, the
operation is quite heavy weight on PA 1.X processors as we need to take
the TLB lock and a TLB broadcast is sent to all processors.This patch removes the purges from flush_dcache_page_asm() and
flush_icache_page_asm.Signed-off-by: John David Anglin
Cc: # v3.16+
Signed-off-by: Helge Deller -
The attached change interchanges the order of purging the TLB and
setting the corresponding page table entry. TLB purges are strongly
ordered. It occurred to me one night that setting the PTE first might
have subtle ordering issues on SMP machines and cause random memory
corruption.A TLB lock guards the insertion of user TLB entries. So after the TLB
is purged, a new entry can't be inserted until the lock is released.
This ensures that the new PTE value is used when the lock is released.Since making this change, no random segmentation faults have been
observed on the Debian hppa buildd servers.Signed-off-by: John David Anglin
Cc: # v3.16+
Signed-off-by: Helge Deller
25 Nov, 2016
4 commits
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This is the second issue I noticed in reviewing the parisc TLB code.
The fic instruction may use either the instruction or data TLB in
flushing the instruction cache. Thus, on machines with a split TLB, we
should also flush the data TLB after setting up the temporary alias
registers.Although this has no functional impact, I changed the pdtlb and pitlb
instructions to consistently use the index register %r0. These
instructions do not support integer displacements.Tested on rp3440 and c8000.
Signed-off-by: John David Anglin
Cc: # v3.16+
Signed-off-by: Helge Deller -
We are still troubled by occasional random segmentation faults and
memory memory corruption on SMP machines. The causes quite a few
package builds to fail on the Debian buildd machines for parisc. When
gcc-6 failed to build three times in a row, I looked again at the TLB
related code. I found a couple of issues. This is the first.In general, we need to ensure page table updates and corresponding TLB
purges are atomic. The attached patch fixes an instance in pci-dma.c
where the page table update was not guarded by the TLB lock.Tested on rp3440 and c8000. So far, no further random segmentation
faults have been observed.Signed-off-by: John David Anglin
Cc: # v3.16+
Signed-off-by: Helge Deller -
Drop the open-coded sched_clock() function and replace it by the provided
GENERIC_SCHED_CLOCK implementation. We have seen quite some hung tasks in the
past, which seem to be fixed by this patch.Signed-off-by: Helge Deller
Cc: # v4.7+
Signed-off-by: Helge Deller -
Helge reported to me the following startup crash:
[ 0.000000] Linux version 4.8.0-1-parisc64-smp (debian-kernel@lists.debian.org) (gcc version 5.4.1 20161019 (GCC) ) #1 SMP Debian 4.8.7-1 (2016-11-13)
[ 0.000000] The 64-bit Kernel has started...
[ 0.000000] Kernel default page size is 4 KB. Huge pages enabled with 1 MB physical and 2 MB virtual size.
[ 0.000000] Determining PDC firmware type: System Map.
[ 0.000000] model 9000/785/J5000
[ 0.000000] Total Memory: 2048 MB
[ 0.000000] Memory: 2018528K/2097152K available (9272K kernel code, 3053K rwdata, 1319K rodata, 1024K init, 840K bss, 78624K reserved, 0K cma-reserved)
[ 0.000000] virtual kernel memory layout:
[ 0.000000] vmalloc : 0x0000000000008000 - 0x000000003f000000 (1007 MB)
[ 0.000000] memory : 0x0000000040000000 - 0x00000000c0000000 (2048 MB)
[ 0.000000] .init : 0x0000000040100000 - 0x0000000040200000 (1024 kB)
[ 0.000000] .data : 0x0000000040b0e000 - 0x0000000040f533e0 (4372 kB)
[ 0.000000] .text : 0x0000000040200000 - 0x0000000040b0e000 (9272 kB)
[ 0.768910] Brought up 1 CPUs
[ 0.992465] NET: Registered protocol family 16
[ 2.429981] Releasing cpu 1 now, hpa=fffffffffffa2000
[ 2.635751] CPU(s): 2 out of 2 PA8500 (PCX-W) at 440.000000 MHz online
[ 2.726692] Setting cache flush threshold to 1024 kB
[ 2.729932] Not-handled unaligned insn 0x43ffff80
[ 2.798114] Setting TLB flush threshold to 140 kB
[ 2.928039] Unaligned handler failed, ret = -1
[ 3.000419] _______________________________
[ 3.000419] < Your System ate a SPARC! Gah! >
[ 3.000419] -------------------------------
[ 3.000419] \ ^__^
[ 3.000419] (__)\ )\/\
[ 3.000419] U ||----w |
[ 3.000419] || ||
[ 9.340055] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-1-parisc64-smp #1 Debian 4.8.7-1
[ 9.448082] task: 00000000bfd48060 task.stack: 00000000bfd50000
[ 9.528040]
[ 10.760029] IASQ: 0000000000000000 0000000000000000 IAOQ: 000000004025d154 000000004025d158
[ 10.868052] IIR: 43ffff80 ISR: 0000000000340000 IOR: 000001ff54150960
[ 10.960029] CPU: 1 CR30: 00000000bfd50000 CR31: 0000000011111111
[ 11.052057] ORIG_R28: 000000004021e3b4
[ 11.100045] IAOQ[0]: irq_exit+0x94/0x120
[ 11.152062] IAOQ[1]: irq_exit+0x98/0x120
[ 11.208031] RP(r2): irq_exit+0xb8/0x120
[ 11.256074] Backtrace:
[ 11.288067] [] cpu_startup_entry+0x1e4/0x598
[ 11.368058] [] smp_callin+0x2c0/0x2f0
[ 11.436308] [] update_curr+0x18c/0x2d0
[ 11.508055] [] dequeue_entity+0x2c0/0x1030
[ 11.584040] [] set_next_entity+0x80/0xd30
[ 11.660069] [] pick_next_task_fair+0x614/0x720
[ 11.740085] [] __schedule+0x394/0xa60
[ 11.808054] [] schedule+0x88/0x118
[ 11.876039] [] rescuer_thread+0x4d4/0x5b0
[ 11.948090] [] kthread+0x1ec/0x248
[ 12.016053] [] end_fault_vector+0x20/0xc0
[ 12.092239] [] _switch_to_ret+0x0/0xf40
[ 12.164044]
[ 12.184036] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-1-parisc64-smp #1 Debian 4.8.7-1
[ 12.244040] Backtrace:
[ 12.244040] [] show_stack+0x68/0x80
[ 12.244040] [] dump_stack+0xec/0x168
[ 12.244040] [] die_if_kernel+0x25c/0x430
[ 12.244040] [] handle_unaligned+0xb48/0xb50
[ 12.244040]
[ 12.632066] ---[ end trace 9ca05a7215c7bbb2 ]---
[ 12.692036] Kernel panic - not syncing: Attempted to kill the idle task!We have the insn 0x43ffff80 in IIR but from IAOQ we should have:
4025d150: 0f f3 20 df ldd,s r19(r31),r31
4025d154: 0f 9f 00 9c ldw r31(ret0),ret0
4025d158: bf 80 20 58 cmpb,*<> r0,ret0,4025d18cCpu0 has just completed running parisc_setup_cache_timing:
[ 2.429981] Releasing cpu 1 now, hpa=fffffffffffa2000
[ 2.635751] CPU(s): 2 out of 2 PA8500 (PCX-W) at 440.000000 MHz online
[ 2.726692] Setting cache flush threshold to 1024 kB
[ 2.729932] Not-handled unaligned insn 0x43ffff80
[ 2.798114] Setting TLB flush threshold to 140 kB
[ 2.928039] Unaligned handler failed, ret = -1From the backtrace, cpu1 is in smp_callin:
void __init smp_callin(void)
{
int slave_id = cpu_now_booting;smp_cpu_init(slave_id);
preempt_disable();flush_cache_all_local(); /* start with known state */
flush_tlb_all_local(NULL);local_irq_enable(); /* Interrupts have been off until now */
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
So, it has just flushed its caches and the TLB. It would seem either the
flushes in parisc_setup_cache_timing or smp_callin have corrupted kernel
memory.The attached patch reworks parisc_setup_cache_timing to remove the races
in setting the cache and TLB flush thresholds. It also corrects the
number of bytes flushed in the TLB calculation.The patch flushes the cache and TLB on cpu0 before starting the
secondary processors so that they are started from a known state.Tested with a few reboots on c8000.
Signed-off-by: John David Anglin
Cc: # v3.18+
Signed-off-by: Helge Deller
23 Nov, 2016
1 commit
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Signed-off-by: Helge Deller
03 Nov, 2016
5 commits
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Signed-off-by: Helge Deller
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LINUX_GATEWAY_ADDR is defined in unistd.h. Let's use it.
Signed-off-by: Helge Deller
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We have one critical section in the syscall entry path in which we switch from
the userspace stack to kernel stack. In the event of an external interrupt, the
interrupt code distinguishes between those two states by analyzing the value of
sr7. If sr7 is zero, it uses the kernel stack. Therefore it's important, that
the value of sr7 is in sync with the currently enabled stack.This patch now disables interrupts while executing the critical section. This
prevents the interrupt handler to possibly see an inconsistent state which in
the worst case can lead to crashes.Interestingly, in the syscall exit path interrupts were already disabled in the
critical section which switches back to the userspace stack.Cc:
Signed-off-by: John David Anglin
Signed-off-by: Helge Deller -
There is no need to trash sr2 and sr3 in the Light-weight syscall (LWS). sr2
already points to kernel space (it's zero in userspace, otherwise syscalls
wouldn't work), and since the LWS code is executed in userspace, we can simply
ignore to preload sr3.Signed-off-by: John David Anglin
Signed-off-by: Helge Deller -
Recent changes to printk require KERN_CONT uses to continue logging messages.
So add KERN_CONT to output of device inventory.Signed-off-by: Helge Deller
12 Oct, 2016
3 commits
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Pull parisc fixes from Helge Deller:
"Some final updates and fixes for this merge window for the parisc
architecture. Changes include:- Fix boot problems with new memblock allocator on rp3410 machine
- Increase initial kernel mapping size for 32- and 64-bit kernels,
this allows to boot bigger kernels which have many modules built-in- Fix kernel layout regarding __gp and move exception table into RO
section- Show trap names in crashes, use extable.h header instead of
module.h"* 'parisc-4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Show trap name in kernel crash
parisc: Zero-initialize newly alloced memblock
parisc: Move exception table into read-only section
parisc: Fix kernel memory layout regarding position of __gp
parisc: Increase initial kernel mapping size
parisc: Migrate exception table users off module.h and onto extable.h -
Show the real trap name when the kernel crashes.
Signed-off-by: Helge Deller
-
Commit 4fe9e1d957e4 ("parisc: Drop bootmem and switch to memblock")
switched to the memblock allocator, but missed to zero-initialize the
newly allocated memblocks. This lead to crashes on some machines like
the rp3410.Fixes: 4fe9e1d957e4 ("parisc: Drop bootmem and switch to memblock")
Signed-off-by: Helge Deller
11 Oct, 2016
2 commits
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Pull misc vfs updates from Al Viro:
"Assorted misc bits and pieces.There are several single-topic branches left after this (rename2
series from Miklos, current_time series from Deepa Dinamani, xattr
series from Andreas, uaccess stuff from from me) and I'd prefer to
send those separately"* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits)
proc: switch auxv to use of __mem_open()
hpfs: support FIEMAP
cifs: get rid of unused arguments of CIFSSMBWrite()
posix_acl: uapi header split
posix_acl: xattr representation cleanups
fs/aio.c: eliminate redundant loads in put_aio_ring_file
fs/internal.h: add const to ns_dentry_operations declaration
compat: remove compat_printk()
fs/buffer.c: make __getblk_slow() static
proc: unsigned file descriptors
fs/file: more unsigned file descriptors
fs: compat: remove redundant check of nr_segs
cachefiles: Fix attempt to read i_blocks after deleting file [ver #2]
cifs: don't use memcpy() to copy struct iov_iter
get rid of separate multipage fault-in primitives
fs: Avoid premature clearing of capabilities
fs: Give dentry to inode_change_ok() instead of inode
fuse: Propagate dentry down to inode_change_ok()
ceph: Propagate dentry down to inode_change_ok()
xfs: Propagate dentry down to inode_change_ok()
... -
Pull protection keys syscall interface from Thomas Gleixner:
"This is the final step of Protection Keys support which adds the
syscalls so user space can actually allocate keys and protect memory
areas with them. Details and usage examples can be found in the
documentation.The mm side of this has been acked by Mel"
* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/pkeys: Update documentation
x86/mm/pkeys: Do not skip PKRU register if debug registers are not used
x86/pkeys: Fix pkeys build breakage for some non-x86 arches
x86/pkeys: Add self-tests
x86/pkeys: Allow configuration of init_pkru
x86/pkeys: Default to a restrictive init PKRU
pkeys: Add details of system call use to Documentation/
generic syscalls: Wire up memory protection keys syscalls
x86: Wire up protection keys system calls
x86/pkeys: Allocation/free syscalls
x86/pkeys: Make mprotect_key() mask off additional vm_flags
mm: Implement new pkey_mprotect() system call
x86/pkeys: Add fault handling for PF_PK page fault bit
09 Oct, 2016
3 commits
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Since BUILDTIME_EXTABLE_SORT is enabled, the exception table can move
into the read-only section.Signed-off-by: Helge Deller
-
Architecturally we need to keep __gp below 0x1000000.
But because of ftrace and tracepoint support, the RO_DATA_SECTION now gets much
bigger than it was before. By moving the linkage tables before RO_DATA_SECTION
we can avoid that __gp gets positioned at a too high address.Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Helge Deller -
Increase the initial kernel default page mapping size for 64-bit kernels to
64 MB and for 32-bit kernels to 32 MB.Due to the additional support of ftrace, tracepoint and huge pages the kernel
size can exceed the sizes we used up to now.Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Helge Deller
08 Oct, 2016
7 commits
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This file was only including module.h for exception table related
functions. We've now separated that content out into its own file
"extable.h" so now move over to that and avoid all the extra header
content in module.h that we don't really need to compile this file.Cc: "James E.J. Bottomley"
Cc: Helge Deller
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Paul Gortmaker
Signed-off-by: Helge Deller -
Merge updates from Andrew Morton:
- fsnotify updates
- ocfs2 updates
- all of MM
* emailed patches from Andrew Morton : (127 commits)
console: don't prefer first registered if DT specifies stdout-path
cred: simpler, 1D supplementary groups
CREDITS: update Pavel's information, add GPG key, remove snail mail address
mailmap: add Johan Hovold
.gitattributes: set git diff driver for C source code files
uprobes: remove function declarations from arch/{mips,s390}
spelling.txt: "modeled" is spelt correctly
nmi_backtrace: generate one-line reports for idle cpus
arch/tile: adopt the new nmi_backtrace framework
nmi_backtrace: do a local dump_stack() instead of a self-NMI
nmi_backtrace: add more trigger_*_cpu_backtrace() methods
min/max: remove sparse warnings when they're nested
Documentation/filesystems/proc.txt: add more description for maps/smaps
mm, proc: fix region lost in /proc/self/smaps
proc: fix timerslack_ns CAP_SYS_NICE check when adjusting self
proc: add LSM hook checks to /proc//timerslack_ns
proc: relax /proc//timerslack_ns capability requirements
meminfo: break apart a very long seq_printf with #ifdefs
seq/proc: modify seq_put_decimal_[u]ll to take a const char *, not char
proc: faster /proc/*/status
... -
Pull parisc updates from Helge Deller:
"Changes include:- Fix boot of 32bit SMP kernel (initial kernel mapping was too small)
- Added hardened usercopy checks
- Drop bootmem and switch to memblock and NO_BOOTMEM implementation
- Drop the BROKEN_RODATA config option (and thus remove the relevant
code from the generic headers and files because parisc was the last
architecture which used this config option)- Improve segfault reporting by printing human readable error strings
- Various smaller changes, e.g. dwarf debug support for assembly
code, update comments regarding copy_user_page_asm, switch to
kmalloc_array()"* 'parisc-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Increase KERNEL_INITIAL_SIZE for 32-bit SMP kernels
parisc: Drop bootmem and switch to memblock
parisc: Add hardened usercopy feature
parisc: Add cfi_startproc and cfi_endproc to assembly code
parisc: Move hpmc stack into page aligned bss section
parisc: Fix self-detected CPU stall warnings on Mako machines
parisc: Report trap type as human readable string
parisc: Update comment regarding implementation of copy_user_page_asm
parisc: Use kmalloc_array() in add_system_map_addresses()
parisc: Check return value of smp_boot_one_cpu()
parisc: Drop BROKEN_RODATA config option -
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 -
This came to light when implementing native 64-bit atomics for ARCv2.
The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
to check whether atomic64_dec_if_positive() is available. It seems it
was needed when not every arch defined it. However as of current code
the Kconfig option seems needless- for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
generic definition of API is present lib/atomic64.c
- arches with native 64-bit atomics select it in arch/*/Kconfig and
define the API in their headersSo I see no point in keeping the Kconfig option
Compile tested for:
- blackfin (CONFIG_GENERIC_ATOMIC64)
- x86 (!CONFIG_GENERIC_ATOMIC64)
- ia64Link: http://lkml.kernel.org/r/1473703083-8625-3-git-send-email-vgupta@synopsys.com
Signed-off-by: Vineet Gupta
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Matt Turner
Cc: Russell King
Cc: Catalin Marinas
Cc: Will Deacon
Cc: Ralf Baechle
Cc: "James E.J. Bottomley"
Cc: Helge Deller
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: Martin Schwidefsky
Cc: Heiko Carstens
Cc: "David S. Miller"
Cc: Chris Metcalf
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: "H. Peter Anvin"
Cc: Vineet Gupta
Cc: Zhaoxiu Zeng
Cc: Linus Walleij
Cc: Alexander Potapenko
Cc: Andrey Ryabinin
Cc: Herbert Xu
Cc: Ming Lin
Cc: Arnd Bergmann
Cc: Geert Uytterhoeven
Cc: Peter Zijlstra
Cc: Borislav Petkov
Cc: Andi Kleen
Cc: Boqun Feng
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Increase the initial kernel default page mapping size for SMP kernels to 32MB
and add a runtime check which panics early if the kernel is bigger than the
initial mapping size.This fixes boot crashes of 32bit SMP kernels. Due to the introduction of huge
page support in kernel 4.4 and it's required initial kernel layout in memory, a
32bit SMP kernel usually got bigger (in layout, not size) than 16MB.Cc: stable@vger.kernel.org #4.4+
Signed-off-by: Helge Deller
07 Oct, 2016
2 commits
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Memblock is the standard kernel boot-time memory tracker/allocator. Use it
instead of the bootmem allocator. This allows using kmemleak, CMA and
other features.Signed-off-by: Helge Deller
-
Add hardened usercopy checks to parisc architecture and clean up
indenting.Signed-off-by: Helge Deller
06 Oct, 2016
2 commits
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Add ENTRY_CFI() and ENDPROC_CFI() macros for dwarf debug info and
convert assembly users to new macros.Signed-off-by: Helge Deller
-
Do not reserve space in data section for hpmc stack, instead move it
into the page aligned bss section.Signed-off-by: Helge Deller
26 Sep, 2016
1 commit
-
The config option HAVE_UNSTABLE_SCHED_CLOCK is set automatically when compiling
for SMP. There is no need to clear the stable-clock flag via
clear_sched_clock_stable() when starting secondary CPUs, and even worse,
clearing it triggers wrong self-detected CPU stall warnings on 64bit Mako
machines.Signed-off-by: Helge Deller
Cc: stable@vger.kernel.org # 4.7+
25 Sep, 2016
1 commit
-
When faulting on some trap, the kernel currently reports in dmesg:
do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000]
vm_start = 0x00922000, vm_end = 0x00aed000With this change the trap type additionally gets reported as human readable
string which makes it simpler to recognize the type of problem:do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000]
trap #6: Instruction TLB miss fault, vm_start = 0x00922000, vm_end = 0x00aed000Signed-off-by: Helge Deller
21 Sep, 2016
3 commits
-
The attached patch describes the current implementation of
copy_user_page_asm(). It is possible to implement this routine using
either the kernel page mappings or equivalent aliases. I tested both
and decided the former was more efficient.Signed-off-by: John David Anglin
Signed-off-by: Helge Deller -
* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".This issue was detected by using the Coccinelle software.
* Replace the specification of a data type by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.Signed-off-by: Markus Elfring
Signed-off-by: Helge Deller -
Check return value of smp_boot_one_cpu() whether CPU could be brought up.
Reported-by: John David Anglin
Signed-off-by: Helge Deller
