The ftrace_regs_caller() trampoline does something 'funny' when there
is a direct-caller present. In that case it stuffs the 'direct-caller'
address on the return stack and then exits the function. This then
results in 'returning' to the direct-caller with the exact registers
we came in with -- an indirect tail-call without using a register.
This however (rightfully) confuses objtool because the function shares
a few instruction in order to have a single exit path, but the stack
layout is different for them, depending through which path we came
there.
This is currently cludged by forcing the stack state to the non-direct
case, but this generates actively wrong (ORC) unwind information for
the direct case, leading to potential broken unwinds.
Fix this issue by fully separating the exit paths. This results in
having to poke a second RET into the trampoline copy, see
ftrace_regs_caller_ret.
This brings us to a second objtool problem, in order for it to
perceive the 'jmp ftrace_epilogue' as a function exit, it needs to be
recognised as a tail call. In order to make that happen,
ftrace_epilogue needs to be the start of an STT_FUNC, so re-arrange
code to make this so.
Finally, a third issue is that objtool requires functions to exit with
the same stack layout they started with, which is obviously violated
in the direct case, employ the new HINT_RET_OFFSET to tell objtool
this is an expected exception.
Together, this results in generating correct ORC unwind information
for the ftrace_regs_caller() function and it's trampoline copies.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.749606694@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Normally objtool ensures a function keeps the stack layout invariant.
But there is a useful exception, it is possible to stuff the return
stack in order to 'inject' a 'call':
push $fun
ret
In this case the invariant mentioned above is violated.
Add an objtool HINT to annotate this and allow a function exit with a
modified stack frame.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.690601403@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Teach objtool a little more about IRET so that we can avoid using the
SAVE/RESTORE annotation. In particular, make the weird corner case in
insn->restore go away.
The purpose of that corner case is to deal with the fact that
UNWIND_HINT_RESTORE lands on the instruction after IRET, but that
instruction can end up being outside the basic block, consider:
if (cond)
sync_core()
foo();
Then the hint will land on foo(), and we'll encounter the restore
hint without ever having seen the save hint.
By teaching objtool about the arch specific exception frame size, and
assuming that any IRET in an STT_FUNC symbol is an exception frame
sized POP, we can remove the use of save/restore hints for this code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.631224674@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Instruction sets can include more or less complex operations which might
not fit the currently defined set of stack_ops.
Combining more than one stack_op provides more flexibility to describe
the behaviour of an instruction. This also reduces the need to define
new stack_ops specific to a single instruction set.
Allow instruction decoders to generate multiple stack_op per
instruction.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200327152847.15294-11-jthierry@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If the prefix of section name is not '.rodata', the following
function call can never return 0.
strcmp(sec->name, C_JUMP_TABLE_SECTION)
So the name comparison is pointless, just remove it.
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some CFI definitions used by generic objtool code have no reason to vary
from one architecture to another. Keep those definitions in generic
code and move the arch-specific ones to a new arch-specific header.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The initial register state is set up by arch specific code. Use the
value the arch code has set when restoring registers from the stack.
Suggested-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The .alternatives section can contain entries with no original
instructions. Objtool will currently crash when handling such an entry.
Just skip that entry, but still give a warning to discourage useless
entries.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a function fails its validation, it might leave a stale state
that will be used for the validation of other functions. That would
cause false warnings on potentially valid functions.
Reset the instruction state before the validation of each individual
function.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
POP operations are already in the code path where the destination
operand is OP_DEST_REG. There is no need to check the operand type
again.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, the check of tools files against kernel equivalent is only
done after every object file has been built. This means one might fix
build issues against outdated headers without seeing a warning about
this.
Check headers before any object is built. Also, make it part of a
FORCE'd recipe so every attempt to build objtool will report the
outdated headers (if any).
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Sometimes, WARN_FUNC() and other users of symbol_by_offset() will
associate the first instruction of a symbol with the symbol preceding
it. This is because symbol->offset + symbol->len is already outside of
the symbol's range.
Fixes: 2a362ecc3e ("objtool: Optimize find_symbol_*() and read_symbols()")
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch corrects the SPDX License Identifier style in
header files related to USB Serial device configuration.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).
Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
The default credit size is 1792 bytes, but the IP mtu is 1500 bytes,
then it has about 290 bytes's waste for each data packet on sdio
transfer path for TX bundle, it will reduce the transmission utilization
ratio for data packet.
This patch enable the small credit size in firmware, firmware will use
the new credit size 1556 bytes, it will increase the transmission
utilization ratio for data packet on TX patch. It results in significant
performance improvement on TX path.
This patch only effect sdio chip, it will not effect PCI, SNOC etc.
Tested with QCA6174 SDIO with firmware
WLAN.RMH.4.4.1-00017-QCARMSWP-1.
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200410061400.14231-3-wgong@codeaurora.org
The transmission utilization ratio for sdio bus for small packet is
slow, because the space and time cost for sdio bus is same for large
length packet and small length packet. So the speed of data for large
length packet is higher than small length.
Test result of different length of data:
data packet(byte) cost time(us) calculated rate(Mbps)
256 28 73
512 33 124
1024 35 234
1792 45 318
14336 168 682
28672 333 688
57344 660 695
This patch change the TX packet from single packet to a large length
bundle packet, max size is 32, it results in significant performance
improvement on TX path.
Also there's a fourth thread "ath10k_tx_complete_wq" added to ath10k as it
improves TCP RX throughput (values in Mbps):
TCP-RX TCP-TX UDP-RX UDP-TX
use workqueue_tx_complete 423 357 448 412
change it to ar->workqueue 410 360 449 414
change it to ar->workqueue_aux 405 339 446 401
This patch only effect sdio chip, it will not effect PCI, SNOC etc.
It only enable bundle for sdio chip.
Tested with QCA6174 SDIO with firmware
WLAN.RMH.4.4.1-00017-QCARMSWP-1.
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200410061400.14231-2-wgong@codeaurora.org
The '==' expression itself is bool, no need to convert it to bool again.
This fixes the following coccicheck warning:
drivers/net/wireless/ath/ath11k/debug.c:198:57-62: WARNING: conversion
to bool not needed here
drivers/net/wireless/ath/ath11k/debug.c:218:58-63: WARNING: conversion
to bool not needed here
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200420123745.4159-1-yanaijie@huawei.com
In order to better organize the main admin-guide index,
place the driver-specific indexes on separate files.
This ensures a more consistent numbering at the main index.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Separate the generic documentation from the driver-specific
parts, and use a better title for the documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The old cards.rst file doesn't exist anymore. Also, it is not
the right reference there, as it should be pointing to the
bttv-specific cardlist.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
While test drivers is probably something that normal users
won't bother, it doesn't hurt to add them to the card list.
This way, all drivers, except for the ones under staging,
would be listed there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The SPI cards are also under the concept of "platform" drivers
as defined at the section introduction.
So, add a SPI card list there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Having a table with a list of all USB drivers seems worth,
and it comes almost for free, as we can just use Kconfig
descriptions (with some adjustments).
So, add a table for that.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Instead of listing "other" PCI card list, just add a list with
the existing drivers (not including sub-drivers).
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The frontend drivers list is incomplete. Update it from
what's there at the Kernel Kconfig files.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The DVB cards.rst file is old and outdated. It also contains
data that are contained on other cardlists. Remove the
duplicated information and split frontends and PCI cards on
separate files.
As all USB cards already have their own card lists, just drop
the old USB data there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
There are several other USB cards. Most of them support just
one device. The only exception is the "pwc" driver. But, as
updates to it are not frequent, let's just place everything
manually into a single file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The siano driver looks like em28xx, except that its cards
are split on 3 drivers.
Add a card list for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The cardlist section is important for some boards, because they
may require extra modprobe parameters.
Improve the docs to mention that.
Thanks-to: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for providing me some PCI IDs
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Several of the existing documents under the media admin-guide
contain build procedures.
Add an specific chapter describing it. This document was
partially inspired on the modifications I made to the bttv.rst
file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The media's admin guide is currently just a group of
not-connected docs.
Add an introduction chapter for it to start making sense
to a random reader.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
It is interesting to have a card list also for cx231xx
driver, as it currently supports 27 different boards.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The USB_DEVICE() list contain some of the product names, but
some are missing, and others are different than the message
printed during device detection.
Update the comments in order to match what the driver prints.
That makes easier to discover what model matches what physical
device.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Instead of using USB_DEVICE() macro directly, use the
DVB_USB_DEVICE() one, as other dvb-usb-v2 devices.
The usage of the new macro makes cleaner and easier to
parse the supported device names in a way that it would
be easily parseable to generate cardlists.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
