... to better explain its purpose after introducing in-place encryption
without bounce buffer.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Since fscrypt users can now indicated if fscrypt_encrypt_page() should
use a bounce page, we can delay the bounce page pool initialization util
it is really needed. That is until fscrypt_operations has no
FS_CFLG_OWN_PAGES flag set.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When CONFIG_TRIM_UNUSED_KSYMS=y and no modules are actually selected,
the adjust_autoksyms.sh script fails with:
sed: can't read .tmp_versions/*.mod: No such file or directory
Let's cope with that case gracefully.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
Rename the FS_CFLG_INPLACE_ENCRYPTION flag to FS_CFLG_OWN_PAGES which,
when set, indicates that the fs uses pages under its own control as
opposed to writeback pages which require locking and a bounce buffer for
encryption.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In case of in-place encryption fscrypt_ctx was allocated but never
released. Since we don't need it for in-place encryption, we skip
allocating it.
Fixes: 1c7dcf69ee ("fscrypt: Add in-place encryption mode")
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Actually use the fs-provided index instead of always using page->index
which is only set for page-cache pages.
Fixes: 9c4bb8a3a9 ("fscrypt: Let fs select encryption index/tweak")
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
These constants are part of the UAPI, so they belong in
include/uapi/linux/fs.h instead of include/linux/fscrypto.h
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
The fscrypt_initalize() function isn't used outside fs/crypto, so
there's no point making it be an exported symbol.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
To avoid namespace collisions, rename get_crypt_info() to
fscrypt_get_crypt_info(). The function is only used inside the
fs/crypto directory, so declare it in the new header file,
fscrypt_private.h.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Multiple bugs were recently fixed in the "set encryption policy" ioctl.
To make it clear that fscrypt_process_policy() and fscrypt_get_policy()
implement ioctls and therefore their implementations must take standard
security and correctness precautions, rename them to
fscrypt_ioctl_set_policy() and fscrypt_ioctl_get_policy(). Make the
latter take in a struct file * to make it consistent with the former.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
SHA256 and ENCRYPTED_KEYS are not needed. CTR shouldn't be needed
either, but I left it for now because it was intentionally added by
commit 71dea01ea2 ("ext4 crypto: require CONFIG_CRYPTO_CTR if ext4
encryption is enabled"). So it sounds like there may be a dependency
problem elsewhere, which I have not been able to identify specifically,
that must be solved before CTR can be removed.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The filesystem level encryption support, currently used by ext4 and f2fs
and proposed for ubifs, does not yet have a dedicated mailing list.
Since no mailing lists were specified in MAINTAINERS, get_maintainer.pl
only recommended to send patches directly to the maintainers and to
linux-kernel. This patch adds linux-fsdevel as the preferred mailing
list for fscrypto patches for the time being.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
qconfig initial slider sizes fix.
On first `make xconfig`, suboption and help panels were hidden.
Now we properly detect the first run, and show those panels.
Reported-by: Jason Vas Dias <jason.vas.dias@gmail.com>
Signed-off-by: Boris Barbulovski <bbarbulovski@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
xconfig - Fix missing 'Show Debug' functionality.
xconfig Help mentions 'Show Debug Info' but it was missing from any
menu.
* Add 'Show debug' menu to the main menu.
* Properly load showDebug settings.
Reported-by: Jason Vas Dias <jason.vas.dias@gmail.com>
Signed-off-by: Boris Barbulovski <bbarbulovski@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
Just prep work to polish and consolidate all the dma-buf related
documenation.
Unfortunately I didn't discover a way to both integrate this new file
into the overall toc while keeping it at the current place. Work
around that by moving it into the overall driver-api/index.rst.
Cc: linux-doc@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Defining static data structures in a header file is wrong because
this causes the data structure to be instantiated once in every .c
file it is included in. Hence move the definition of a static
array from a header file into the only .c file in which it is used.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>
Cc: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Declare the structure mmu_notifier_ops as const as it is only stored in
the ops field of a mmu_notifier structure. The ops field is of type
const struct mmu_notifier_ops *, so mmu_notifier_ops structures having
this property can be declared as const.
Done using coccinelle:
@r1 disable optional_qualifier @
identifier i;
position p;
@@
static struct mmu_notifier_ops i@p = {...};
@ok1@
identifier r1.i;
position p;
struct mmu_rb_handler handler;
@@
handler.mn.ops=&i@p
@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p
@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
static
+const
struct mmu_notifier_ops i={...};
@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct mmu_notifier_ops i;
File size before:
text data bss dec hex filename
3566 72 16 3654 e46
drivers/infiniband/hw/hfi1/mmu_rb.o
File size after:
text data bss dec hex filename
3658 0 16 3674 e5a
drivers/infiniband/hw/hfi1/mmu_rb.o
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Add rvt_div_round_up_mtu() and rvt_div_mtu() routines to
do the computation based on the pmtu and the log_pmtu.
Change divides in qib, hfi1 to use the new inlines.
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Convert to use new swqe put routine.
Reviewed-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Add a helper to release mr references held by
an swqe.
Reviewed-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Do not allocate credit return base and DMA memory for
NUMA nodes without CPUs.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Convert cq completion returns in both rdmavt drivers
to use the new helper.
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This is for use by client drivers to drive
send completions into a CQ.
A new exported table allows for the mapping
of ib_wr_opcode into a ib_wc_opcode.
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Use the standard driver wrapper for QP reference counters.
This makes the code more maintainable.
Fixes: Commit 4d6f85c3fa ("IB/rdmavt, IB/qib, IB/hfi1: Use new QP put get routines")
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Some parts of the code don't use the standard driver
wrapper for memory region reference counters. Use the
standard driver wrapper throughout the code.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Some parts of the code don't use the standard release
wrapper rvt_put_qp() for decrementing and testing
the refcount to then try to use a resource.
Replace this code with the standard driver wrapper.
Fixes: Commit 4d6f85c3fa ("IB/rdmavt, IB/qib, IB/hfi1: Use new QP put get routines")
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The driver should not change the external device request
completed bit when not actually doing an external device
request.
Reviewed-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
In sc_buffer_alloc(), the sc->alloc_lock is released
before calling sc_release_update(), and it is reacquired
after the function call. This causes CPU lock trading.
Fix it by not dropping the lock before calling
sc_release_update().
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The s_cur_sge field in the qp structure holds a pointer to the
SGE of the currently processed WQE. It assumes the protection
of the RVT_S_BUSY flag to prevent the changing of this field
while the send engine is using it. This scheme works as long
as there is only one instance of the send engine running at a
time.
Scaling of the send engine to multiple cores would break this
assumption as there could be multiple instances of the send engine
running on different CPUs. This opens a window where the QP's
RVT_S_BUSY flag is not set but the send engine is still running.
To prevent accidental changing of the s_cur_sge pointer, the QP's
dependence on it is removed. The SGE pointer is now stored in the
verbs_txreq, which is a per-packet data structure. This ensures
that each individual packet has it's own pointer, which is setup
while the RVT_S_BUSY flag is set.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Low power QSFP AOC cables require a different SerDes
Tx PLL bandwidth setting than the default. The
8051 firmware does not know the details, so the driver
needs to tell the firmware through a special setting.
Reviewed-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The struct hfi1_affinity is not used anymore.
We use the struct hfi1_affinity_node and hfi1_affinity_node_list
instead.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The qp->s_cur_size field assumes that the S_BUSY bit protects
the field from modification after the slock is dropped. Scaling the
send engine to multiple cores would break that assumption.
Correct the issue by carrying the payload size in the txreq structure.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Don Hiatt <don.hiatt@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Previously tools like hfi1stats had to access these counters through
debugfs, which often caused permission issue for non-root users. It is
not always acceptable to change the debugfs mounting permission due
to security concerns. When exposed under the IB stats interface, the
counters are universally readable by default.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jianxin Xiong <jianxin.xiong@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Split rdmavt traces into separate files to preserve the original
hierarchy since only one trace sub system may now be defined per header
file.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
For the received packets with payload less or equal 8DWS
RxDmaDataFifoRdUncErr is not reported. There is set RHF.EccErr
if the header is not suppressed. When such packet is detected
on the send side the header suppression mechanism is disabled
by clearing SH bit in the packet header.
Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Jakub Pawlak <jakub.pawlak@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Both the 8051 memory and LCB register access require multiple
steps and coordination with the driver. This cannot be safely
done with resource0 alone.
The 8051 memory is exported read-only. LCB is exported read/write.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
qp->r_aflags is already protected by qp->r_lock, therefore,
test_and_clear_bit() doesn't need to be atomic. Profile
shows this function call is costly.
Change the test_and_clear_bit() call to use the non-atomic
variant.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
When reading multiple dc8051 data memory locations
at once, the read enabled field must be toggled
at every address change. Do that by writing only
the address first, then writing the enable.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Add the ability to read the new EPROM format.
Reviewed-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Pull MIPS fixes from Ralf Baechle:
"Two more MIPS fixes for 4.9:
- RTC: Return -ENODEV so an external RTC will be tried
- Fix mask of GPE frequency
These two have been tested on Imagination's automated test system and
also both received positive reviews on the linux-mips mailing list"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: Lantiq: Fix mask of GPE frequency
MIPS: Return -ENODEV from weak implementation of rtc_mips_set_time
Dump and reset doesn't work unless cmpxchg64() is used both from packet
and control plane paths. This approach is going to be slow though.
Instead, use a percpu seqcount to fetch counters consistently, then
subtract bytes and packets in case a reset was requested.
The cpu that running over the reset code is guaranteed to own this stats
exclusively, we have to turn counters into signed 64bit though so stats
update on reset don't get wrong on underflow.
This patch is based on original sketch from Eric Dumazet.
Fixes: 43da04a593 ("netfilter: nf_tables: atomic dump and reset for stateful objects")
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
find_idlest_group() only compares the runnable_load_avg when looking
for the least loaded group. But on fork intensive use case like
hackbench where tasks blocked quickly after the fork, this can lead to
selecting the same CPU instead of other CPUs, which have similar
runnable load but a lower load_avg.
When the runnable_load_avg of 2 CPUs are close, we now take into
account the amount of blocked load as a 2nd selection factor. There is
now 3 zones for the runnable_load of the rq:
- [0 .. (runnable_load - imbalance)]:
Select the new rq which has significantly less runnable_load
- [(runnable_load - imbalance) .. (runnable_load + imbalance)]:
The runnable loads are close so we use load_avg to chose
between the 2 rq
- [(runnable_load + imbalance) .. ULONG_MAX]:
Keep the current rq which has significantly less runnable_load
The scale factor that is currently used for comparing runnable_load,
doesn't work well with small value. As an example, the use of a
scaling factor fails as soon as this_runnable_load == 0 because we
always select local rq even if min_runnable_load is only 1, which
doesn't really make sense because they are just the same. So instead
of scaling factor, we use an absolute margin for runnable_load to
detect CPUs with similar runnable_load and we keep using scaling
factor for blocked load.
For use case like hackbench, this enable the scheduler to select
different CPUs during the fork sequence and to spread tasks across the
system.
Tests have been done on a Hikey board (ARM based octo cores) for
several kernel. The result below gives min, max, avg and stdev values
of 18 runs with each configuration.
The patches depend on the "no missing update_rq_clock()" work.
hackbench -P -g 1
ea86cb4b767dc603c902 v4.8 v4.8+patches
min 0.049 0.050 0.051 0,048
avg 0.057 0.057(0%) 0.057(0%) 0,055(+5%)
max 0.066 0.068 0.070 0,063
stdev +/-9% +/-9% +/-8% +/-9%
More performance numbers here:
https://lkml.kernel.org/r/20161203214707.GI20785@codeblueprint.co.uk
Tested-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: kernellwp@gmail.com
Cc: umgwanakikbuti@gmail.com
Cc: yuyang.du@intel.comc
Link: http://lkml.kernel.org/r/1481216215-24651-3-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
During fork, the utilization of a task is init once the rq has been
selected because the current utilization level of the rq is used to
set the utilization of the fork task. As the task's utilization is
still 0 at this step of the fork sequence, it doesn't make sense to
look for some spare capacity that can fit the task's utilization.
Furthermore, I can see perf regressions for the test:
hackbench -P -g 1
because the least loaded policy is always bypassed and tasks are not
spread during fork.
With this patch and the fix below, we are back to same performances as
for v4.8. The fix below is only a temporary one used for the test
until a smarter solution is found because we can't simply remove the
test which is useful for others benchmarks
| @@ -5708,13 +5708,6 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t
|
| avg_cost = this_sd->avg_scan_cost;
|
| - /*
| - * Due to large variance we need a large fuzz factor; hackbench in
| - * particularly is sensitive here.
| - */
| - if ((avg_idle / 512) < avg_cost)
| - return -1;
| -
| time = local_clock();
|
| for_each_cpu_wrap(cpu, sched_domain_span(sd), target, wrap) {
Tested-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: kernellwp@gmail.com
Cc: umgwanakikbuti@gmail.com
Cc: yuyang.du@intel.comc
Link: http://lkml.kernel.org/r/1481216215-24651-2-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
3cded41794 ("x86/paravirt: Optimize native pv_lock_ops.vcpu_is_preempted()")
introduced a paravirt op with bool return type [*]
It turns out that the PVOP_CALL*() macros miscompile when rettype is
bool. Code that looked like:
83 ef 01 sub $0x1,%edi
ff 15 32 a0 d8 00 callq *0xd8a032(%rip) # ffffffff81e28120 <pv_lock_ops+0x20>
84 c0 test %al,%al
ended up looking like so after PVOP_CALL1() was applied:
83 ef 01 sub $0x1,%edi
48 63 ff movslq %edi,%rdi
ff 14 25 20 81 e2 81 callq *0xffffffff81e28120
48 85 c0 test %rax,%rax
Note how it tests the whole of %rax, even though a typical bool return
function only sets %al, like:
0f 95 c0 setne %al
c3 retq
This is because ____PVOP_CALL() does:
__ret = (rettype)__eax;
and while regular integer type casts truncate the result, a cast to
bool tests for any !0 value. Fix this by explicitly truncating to
sizeof(rettype) before casting.
[*] The actual bug should've been exposed in commit:
446f3dc8cc ("locking/core, x86/paravirt: Implement vcpu_is_preempted(cpu) for KVM and Xen guests")
but that didn't properly implement the paravirt call.
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 3cded41794 ("x86/paravirt: Optimize native pv_lock_ops.vcpu_is_preempted()")
Link: http://lkml.kernel.org/r/20161208154349.346057680@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
