This patch fixes the following error in sb_pc_mp.c-
drivers/staging/sb105x/sb_pci_mp.c:546 mp_startup() error: we previously assumed 'info->tty' could be null (see line 525)
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hopefully this isn't too late for 3.12.
In commit 7dc19d5aff (convert shrinkers to new count/scan API)
the return value to PURGE_ALL_CACHES was dropped, causing -EPERM
to always be returned.
This patch re-adds the ret assignment, setting it to the the
ashmem_shrink_count(), which is the lru_count.
(Sorry this was missed in the review!)
Fixes: 7dc19d5aff ("convert shrinkers to new count/scan API")
Cc: Colin Cross <ccross@android.com>
Cc: Android Kernel Team <kernel-team@android.com>
Cc: Glauber Costa <glommer@openvz.org>
Reported-by: YongQin Liu <yongqin.liu@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: stable <stable@kernel.org> # 3.12
Acked-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When tests were added to lkdtm that grew the stack frame, the stack
corruption test stopped working. This isolates the test in its own
function, and forces it not to be inlined.
Signed-off-by: Kees Cook <keescook@chromium.org>
Fixes: cc33c537c1 ("lkdtm: add "EXEC_*" triggers")
Cc: stable <stable@vger.kernel.org> # 3.12
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64c862a8 (devres: add kernel standard devm_k.alloc functions) changed
the default behavior of alloc_dr() to no longer zero the allocated memory. However,
only the devm.k.alloc() function were modified to pass in __GFP_ZERO which leaves
any users of devres_alloc() or __devres_alloc() with potentially wrong assumptions
about memory being zero'd upon allocation.
To fix, add __GFP_ZERO to devres_alloc() calls to preserve previous
behavior of zero'ing memory upon allocation.
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before patch(sysfs: prepare path write for unified regular / bin
file handling), when size of bin file is zero, writting still can
continue, but this patch changes the behaviour.
The worse thing is that firmware loader is broken by this patch,
and user space application can't write to firmware bin file any more
because both firmware loader and drivers can't know at advance how
large the firmware file is and have to set its initialized size as
zero.
This patch fixes the problem and keeps behaviour of writting to bin
as before.
Reported-by: Lothar Waßmann <LW@karo-electronics.de>
Tested-by: Lothar Waßmann <LW@karo-electronics.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
software_resume is being called after deferred_probe_initcall in
drivers base. If the probing of the device that contains the resume
image is deferred, and the system has been instructed to wait for
it to show up, this wait will occur in software_resume. This causes
a deadlock.
Move software_resume into late_initcall_sync so that it happens
after all the other late_initcalls.
Signed-off-by: Russ Dill <Russ.Dill@ti.com>
Acked-by: Pavel Machek <Pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In a recent commit:
commit f455578dd9
Author: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Date: Mon Aug 12 14:14:53 2013 -0300
mtd: nand: pxa3xx: Remove hardcoded mtd name
There's no advantage in using a hardcoded name for the mtd device.
Instead use the provided by the platform_device.
The MTD name was changed to use the one provided by the platform_device.
However, this can be problematic as some users want to set partitions
using the kernel parameter 'mtdparts', where the name is needed.
Therefore, to avoid regressions in users relying in 'mtdparts' we revert
the change and use the previous one 'pxa3xx_nand-0'.
While at it, let's put a big comment and prevent this change from happening
ever again.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Shifting page->index on 32 bit systems was overflowing, causing
data corruption of > 4GB files. Fix this by casting it first.
https://launchpad.net/bugs/1243636
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reported-by: Lars Duesing <lars.duesing@camelotsweb.de>
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
When it fails to allocate a slot, edesc should be free'd before return;
Signed-off-by: Valentin Ilie <valentin.ilie@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Final conversions to configfs for mass storage, acm_ms, and
multi gadgets.
MUSB should now work out of the box on AM335x-based boards
(beagle bone white and black) with DMA thanks to Sebastian's
work.
We can now enable VERBOSE_DEBUG on builds of drivers/usb/gadget/
by selecting CONFIG_USB_GADGET_VERBOSE.
s3c-hsotg got quite a few non-critical fixes but also learned
a few new tricks (isochronous transfers, multi count support).
The Marvel USB3 Controller driver got a memory leak fix.
devm_usb_get_phy() learned not to return NULL, ever.
Other than these patches, we have the usual set of cleanups
ranging from removal of unnecessary *_set_drvdata() to using
SIMPLE_DEV_PM_OPS.
Signed-of-by: Felipe Balbi <balbi@ti.com>
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Merge tag 'usb-for-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next
Felipe writes:
usb: patches for v3.13
Final conversions to configfs for mass storage, acm_ms, and
multi gadgets.
MUSB should now work out of the box on AM335x-based boards
(beagle bone white and black) with DMA thanks to Sebastian's
work.
We can now enable VERBOSE_DEBUG on builds of drivers/usb/gadget/
by selecting CONFIG_USB_GADGET_VERBOSE.
s3c-hsotg got quite a few non-critical fixes but also learned
a few new tricks (isochronous transfers, multi count support).
The Marvel USB3 Controller driver got a memory leak fix.
devm_usb_get_phy() learned not to return NULL, ever.
Other than these patches, we have the usual set of cleanups
ranging from removal of unnecessary *_set_drvdata() to using
SIMPLE_DEV_PM_OPS.
Signed-of-by: Felipe Balbi <balbi@ti.com>
Cleanup function information block used as a modify pci function
parameter. Change reserved members to be anonymous. Fix the size
of the struct and add proper alignment information. Also put the
FIB on the stack.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add debugfs entries regardless of CONFIG_PCI_DEBUG.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cleanup arch specific pci messages. Remove unhelpful messages and
replace others with entries in the debugfs.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add four more defconfigs which we maintained outside of
the kernel tree for no good reason.
Inside of the kernel tree they can be easily used:
make whatever_defconfig
"make help" shows the available defconfigs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Optimize this_cpu_* functions for 64 bit by making use of new instructions
that came with the interlocked-access facility 1 (load-and-*) and the
general-instructions-extension facility (asi, agsi).
That way we get rid of the compare-and-swap loop in most cases.
Code size reduction (defconfig, -march=z196): 11,555 bytes.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the special cases for the this_cpu_* functions for 32 bit
in order to make it easier to add additional code for 64 bit.
32 bit will use the generic implementation.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make psw32_user_bits a constant value again.
This is a leftover of the code which allowed to run the kernel either
in primary or home space which got removed with 9a905662 "s390/uaccess:
always run the kernel in home space".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix the following bugs:
- When returning from a signal the signal handler copies the saved psw mask
from user space and uses parts of it. Especially it restores the RI bit
unconditionally. If however the machine doesn't support RI, or RI is
disabled for the task, the last lpswe instruction which returns to user
space will generate a specification exception.
To fix this check if the RI bit is allowed to be set and kill the task
if not.
- In the compat mode signal handler code the RI bit of the psw mask gets
propagated to the mask of the return psw: if user space enables RI in the
signal handler, RI will also be enabled after the signal handler is
finished.
This is a different behaviour than with 64 bit tasks. So change this to
match the 64 bit semantics, which restores the original RI bit value.
- Fix similar oddities within the ptrace code as well.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The FPC_VALID_MASK has been used to check the validity of the value
to be loaded into the floating-point-control register. With the
introduction of the floating-point extension facility and the
decimal-floating-point additional bits have been defined which need
to be checked in a non straight forward way. So far these bits have
been ignored which can cause an incorrect results for decimal-
floating-point operations, e.g. an incorrect rounding mode to be
set after signal return.
The static check with the FPC_VALID_MASK is replaced with a trial
load of the floating-point-control value, see test_fp_ctl.
In addition an information leak with the padding word between the
floating-point-control word and the floating-point registers in
the s390_fp_regs is fixed.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is a debugging leftover from git commit 4d334fd155
"s390/3270: asynchronous size sensing" in raw3270_reset_device_cb.
Under z/VM the diagnose 0x210 can be used to find the correct
size of the 3270 terminal.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If a machine has no hardware support for the xts-aes or ctr-aes algorithms
they are not registered in aes_s390_init. But aes_s390_fini unconditionally
unregisters the algorithms which causes crypto_remove_alg to crash.
Add two flag variables to remember if xts-aes and ctr-aes have been added.
Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make smatch happy and remove this warning:
drivers/s390/char/raw3270.c:347 raw3270_irq() error: we previously
assumed 'rq' could be null (see line 342)
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch fixes the following smatch warning:
monwrite_diag() error: strcpy() '"LNXAPPL"' too large for 'id.prod_nr'
(8 vs 7)
Using strcpy() is wrong, because it also copies the terminating null
byte, but in this case the extra copied null byte will be overwritten
right after the strcpy(), so there is no real problem here.
Use strncpy() to fix the warning.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Just change the type of "len" to unsigned int so the compiler can prove
that we don't have a buffer overflow (and generates less code).
We get rid of these:
In function 'copy_from_user',
inlined from 'appldata_interval_handler' at
arch/s390/appldata/appldata_base.c:265:
uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
with attribute warning: copy_from_user() buffer size is not provably
correct
In function 'copy_from_user',
inlined from 'appldata_timer_handler' at
arch/s390/appldata/appldata_base.c:225:
uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
with attribute warning: copy_from_user() buffer size is not provably
correct
In function 'copy_from_user',
inlined from 'appldata_generic_handler' at
arch/s390/appldata/appldata_base.c:333:
uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
with attribute warning: copy_from_user() buffer size is not provably
correct
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of these two warnings:
In function 'copy_from_user',
inlined from 'cmm_timeout_handler' at arch/s390/mm/cmm.c:310:
uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
with attribute warning: copy_from_user() buffer size is not provably
correct
In function 'copy_from_user',
inlined from 'cmm_pages_handler' at arch/s390/mm/cmm.c:270:
uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
with attribute warning: copy_from_user() buffer size is not provably
correct
Change the "len" type to unsigned int, so we can make sure that there is no
buffer overflow. This also generates less code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of this one:
arch/s390/kernel/cache.c: In function 'cache_build_info':
arch/s390/kernel/cache.c:144: warning: 'private' may be used uninitialized
in this function
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Instead of returnin the number of bytes not copied and/or -EFAULT let the
signal handler helper functions always return -EFAULT if a user space
access failed.
This doesn't fix a bug in the current code, but makes is harder to get it
wrong in the future.
Also "smatch" won't complain anymore about the fact that the number of
remaining bytes gets returned instead of -EFAULT.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Missing parenthesis may cause problems when using the defines
together with operations of higher precedence.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently zfpcdump can only collect registers for up to CONFIG_NR_CPUS
CPUss. This dependency is not necessary. So remove it by dynamically
allocating the save area array.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Steven Rostedt noted that s390 is the only architecture which calls
ftrace_push_return_trace() before ftrace_graph_entry() and therefore has
the small advantage that trace.depth gets initialized automatically.
However this small advantage isn't worth the difference and possible subtle
breakage that may result from this.
So change s390 to have the same function call order like all other
architectures: first ftrace_graph_entry(), then ftrace_push_return_trace()
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of this compile warning:
arch/s390/kernel/crash_dump.c: In function 'copy_from_realmem':
arch/s390/kernel/crash_dump.c:48:6: warning: unused variable 'rc'
[-Wunused-variable]
int rc;
^
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The type of 'v->counter' is always 'int', and related inline assembly
code also process 'int', so use 'unsigned int' instead of 'unsigned
long' for the 'mask'.
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If [__]get_user_pages_fast() gets called with nr_pages == 0, the current
code would walk the page tables and pin as many pages until the first
invalid pte (or the kernel crashed while writing struct page pointers to
the pages array).
So let's handle at least the nr_pages == 0 case correctly and exit early.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Just call __get_user_pages_fast() from get_user_pages_fast() like powerpc.
This saves a lot of duplicated code.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With dirty and referenced bits implemented in software it is unnecessary
to initialize the storage key for every page. With this patch not a single
storage key operation is done for a system that does not use KVM.
For KVM set_pte_at/pgste_set_key will do the initialization for the guest
view of the storage key when the mapping for the page is established in
the host.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The prolog of functions generated by the bpf jit compiler uses an
instruction sequence with an "ahi" instruction to create stack space
instead of using an "aghi" instruction. Using the 32-bit "ahi" is not
wrong as the stack we are operating on is an order-4 allocation which
is always aligned to 16KB. But it is more consistent to use an "aghi"
as the stack pointer is a 64-bit value.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- turn some macros into functions
- merge two almost identical versions for 32/64 bit
- add BUILD_BUG_ON() check to make sure the passed in array is large enough
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When quiescing an eadm subchannel make sure that outstanding IO is
cleared and potential timeout handlers are canceled.
Reviewed-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Implement architecture-specific functionality when a PCI device is
doing a hibernate transition.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Simplify the uaccess code by removing the user_mode=home option.
The kernel will now always run in the home space mode.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
find_first_bit_left() and friends have nothing to do with the normal
LSB0 bit numbering for big endian machines used in Linux (least
significant bit has bit number 0).
Instead they use MSB0 bit numbering, where the most signficant bit has
bit number 0. So rename find_first_bit_left() and friends to
find_first_bit_inv(), to avoid any confusion.
Also provide inv versions of set_bit, clear_bit and test_bit.
This also removes the confusing use of e.g. set_bit() in airq.c which
uses a "be_to_le" bit number conversion, which could imply that instead
set_bit_le() could be used. But that is entirely wrong since the _le
bitops variant uses yet another bit numbering scheme.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since z9 109 we have the flogr instruction which can be used to implement
optimized versions of __ffs, ffs, __fls, fls and fls64.
So implement and use them, instead of the generic variants.
This reduces the size of the kernel image (defconfig, -march=z9-109)
by 19,648 bytes.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Just like all other architectures we should use out-of-line find bit
operations, since the inline variant bloat the size of the kernel image.
And also like all other architecures we should only supply optimized
variants of the __ffs, ffs, etc. primitives.
Therefore this patch removes the inlined s390 find bit functions and uses
the generic out-of-line variants instead.
The optimization of the primitives follows with the next patch.
With this patch also the functions find_first_bit_left() and
find_next_bit_left() have been reimplemented, since logically, they are
nothing else but a find_first_bit()/find_next_bit() implementation that
use an inverted __fls() instead of __ffs().
Also the restriction that these functions only work on machines which
support the "flogr" instruction is gone now.
This reduces the size of the kernel image (defconfig, -march=z9-109)
by 144,482 bytes.
Alone the size of the function build_sched_domains() gets reduced from
7 KB to 3,5 KB.
We also git rid of unused functions like find_first_bit_le()...
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Refactor direct debug level comparisons with the (internal) s390db->level
member. Use the debug_level_enabled() function instead.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the debug_level_enabled() function to check if debug events for
a particular level would be logged. This might help to save cycles
for debug events that require additional information collection.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since zEC12 we have the interlocked-access facility 2 which allows to
use the instructions ni/oi/xi to update a single byte in storage with
compare-and-swap semantics.
So change set_bit(), clear_bit() and change_bit() to generate such code
instead of a compare-and-swap loop (or using the load-and-* instruction
family), if possible.
This reduces the text segment by yet another 8KB (defconfig).
Alternatively the long displacement variants niy/oiy/xiy could have
been used, but the extended displacement field is usually not needed
and therefore would only increase the size of the text segment again.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove CONFIG_SMP from bitops code. This reduces the C code significantly
but also generates better code for the SMP case.
This means that for !CONFIG_SMP set_bit() and friends now also have
compare and swap semantics (read: more code). However nobody really cares
for !CONFIG_SMP and this is the trade-off to simplify the SMP code which we
do care about.
The non-atomic bitops like __set_bit() now generate also better code
because the old code did not have a __builtin_contant_p() check for the
CONFIG_SMP case and therefore always generated the inline assembly variant.
However the inline assemblies for the non-atomic case now got completely
removed since gcc can produce better code, which accesses less memory
operands.
test_bit() got also a bit simplified since it did have a
__builtin_constant_p() check, however two identical code pathes for each
case (written differently).
In result this mainly reduces the to be maintained code but is not very
relevant for code generation, since there are not many non-atomic bitops
usages that we care about.
(code reduction defconfig kernel image before/after: 560 bytes).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
