Notable changes:
- A large series to rewrite our SLB miss handling, replacing a lot of fairly
complicated asm with much fewer lines of C.
- Following on from that, we now maintain a cache of SLB entries for each
process and preload them on context switch. Leading to a 27% speedup for our
context switch benchmark on Power9.
- Improvements to our handling of SLB multi-hit errors. We now print more debug
information when they occur, and try to continue running by flushing the SLB
and reloading, rather than treating them as fatal.
- Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).
- Add support for physical memory up to 2PB in the linear mapping on 64-bit
Book3S. We only support up to 512TB as regular system memory, otherwise the
percpu allocator runs out of vmalloc space.
- Add stack protector support for 32 and 64-bit, with a per-task canary.
- Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.
- Support recognising "big cores" on Power9, where two SMT4 cores are presented
to us as a single SMT8 core.
- A large series to cleanup some of our ioremap handling and PTE flags.
- Add a driver for the PAPR SCM (storage class memory) interface, allowing
guests to operate on SCM devices (acked by Dan).
- Changes to our ftrace code to handle very large kernels, where we need to use
a trampoline to get to ftrace_caller().
Many other smaller enhancements and cleanups.
Thanks to:
Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda
Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao,
Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel
Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari
Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan
Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael
Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran,
Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam
Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell,
Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant
Hegde, YueHaibing, zhong jiang,
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Merge tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- A large series to rewrite our SLB miss handling, replacing a lot of
fairly complicated asm with much fewer lines of C.
- Following on from that, we now maintain a cache of SLB entries for
each process and preload them on context switch. Leading to a 27%
speedup for our context switch benchmark on Power9.
- Improvements to our handling of SLB multi-hit errors. We now print
more debug information when they occur, and try to continue running
by flushing the SLB and reloading, rather than treating them as
fatal.
- Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).
- Add support for physical memory up to 2PB in the linear mapping on
64-bit Book3S. We only support up to 512TB as regular system
memory, otherwise the percpu allocator runs out of vmalloc space.
- Add stack protector support for 32 and 64-bit, with a per-task
canary.
- Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.
- Support recognising "big cores" on Power9, where two SMT4 cores are
presented to us as a single SMT8 core.
- A large series to cleanup some of our ioremap handling and PTE
flags.
- Add a driver for the PAPR SCM (storage class memory) interface,
allowing guests to operate on SCM devices (acked by Dan).
- Changes to our ftrace code to handle very large kernels, where we
need to use a trampoline to get to ftrace_caller().
And many other smaller enhancements and cleanups.
Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton
Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin
Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy,
Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham
R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao,
Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh
Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann,
Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver
O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab,
Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan
Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel
Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang"
* tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits)
Revert "selftests/powerpc: Fix out-of-tree build errors"
powerpc/msi: Fix compile error on mpc83xx
powerpc: Fix stack protector crashes on CPU hotplug
powerpc/traps: restore recoverability of machine_check interrupts
powerpc/64/module: REL32 relocation range check
powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd
selftests/powerpc: Add a test of wild bctr
powerpc/mm: Fix page table dump to work on Radix
powerpc/mm/radix: Display if mappings are exec or not
powerpc/mm/radix: Simplify split mapping logic
powerpc/mm/radix: Remove the retry in the split mapping logic
powerpc/mm/radix: Fix small page at boundary when splitting
powerpc/mm/radix: Fix overuse of small pages in splitting logic
powerpc/mm/radix: Fix off-by-one in split mapping logic
powerpc/ftrace: Handle large kernel configs
powerpc/mm: Fix WARN_ON with THP NUMA migration
selftests/powerpc: Fix out-of-tree build errors
powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected
powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64
powerpc/time: isolate scaled cputime accounting in dedicated functions.
...
Here is the big set of char/misc patches for 4.20-rc1.
Loads of things here, we have new code in all of these driver
subsystems:
fpga
stm
extcon
nvmem
eeprom
hyper-v
gsmi
coresight
thunderbolt
vmw_balloon
goldfish
soundwire
along with lots of fixes and minor changes to other small drivers.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big set of char/misc patches for 4.20-rc1.
Loads of things here, we have new code in all of these driver
subsystems:
- fpga
- stm
- extcon
- nvmem
- eeprom
- hyper-v
- gsmi
- coresight
- thunderbolt
- vmw_balloon
- goldfish
- soundwire
along with lots of fixes and minor changes to other small drivers.
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (245 commits)
Documentation/security-bugs: Clarify treatment of embargoed information
lib: Fix ia64 bootloader linkage
MAINTAINERS: Clarify UIO vs UIOVEC maintainer
docs/uio: fix a grammar nitpick
docs: fpga: document programming fpgas using regions
fpga: add devm_fpga_region_create
fpga: bridge: add devm_fpga_bridge_create
fpga: mgr: add devm_fpga_mgr_create
hv_balloon: Replace spin_is_locked() with lockdep
sgi-xp: Replace spin_is_locked() with lockdep
eeprom: New ee1004 driver for DDR4 memory
eeprom: at25: remove unneeded 'at25_remove'
w1: IAD Register is yet readable trough iad sys file. Fix snprintf (%u for unsigned, count for max size).
misc: mic: scif: remove set but not used variables 'src_dma_addr, dst_dma_addr'
misc: mic: fix a DMA pool free failure
platform: goldfish: pipe: Add a blank line to separate varibles and code
platform: goldfish: pipe: Remove redundant casting
platform: goldfish: pipe: Call misc_deregister if init fails
platform: goldfish: pipe: Move the file-scope goldfish_pipe_dev variable into the driver state
platform: goldfish: pipe: Move the file-scope goldfish_pipe_miscdev variable into the driver state
...
Pull siginfo updates from Eric Biederman:
"I have been slowly sorting out siginfo and this is the culmination of
that work.
The primary result is in several ways the signal infrastructure has
been made less error prone. The code has been updated so that manually
specifying SEND_SIG_FORCED is never necessary. The conversion to the
new siginfo sending functions is now complete, which makes it
difficult to send a signal without filling in the proper siginfo
fields.
At the tail end of the patchset comes the optimization of decreasing
the size of struct siginfo in the kernel from 128 bytes to about 48
bytes on 64bit. The fundamental observation that enables this is by
definition none of the known ways to use struct siginfo uses the extra
bytes.
This comes at the cost of a small user space observable difference.
For the rare case of siginfo being injected into the kernel only what
can be copied into kernel_siginfo is delivered to the destination, the
rest of the bytes are set to 0. For cases where the signal and the
si_code are known this is safe, because we know those bytes are not
used. For cases where the signal and si_code combination is unknown
the bits that won't fit into struct kernel_siginfo are tested to
verify they are zero, and the send fails if they are not.
I made an extensive search through userspace code and I could not find
anything that would break because of the above change. If it turns out
I did break something it will take just the revert of a single change
to restore kernel_siginfo to the same size as userspace siginfo.
Testing did reveal dependencies on preferring the signo passed to
sigqueueinfo over si->signo, so bit the bullet and added the
complexity necessary to handle that case.
Testing also revealed bad things can happen if a negative signal
number is passed into the system calls. Something no sane application
will do but something a malicious program or a fuzzer might do. So I
have fixed the code that performs the bounds checks to ensure negative
signal numbers are handled"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
signal: Guard against negative signal numbers in copy_siginfo_from_user32
signal: Guard against negative signal numbers in copy_siginfo_from_user
signal: In sigqueueinfo prefer sig not si_signo
signal: Use a smaller struct siginfo in the kernel
signal: Distinguish between kernel_siginfo and siginfo
signal: Introduce copy_siginfo_from_user and use it's return value
signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
signal: Fail sigqueueinfo if si_signo != sig
signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
signal/unicore32: Use force_sig_fault where appropriate
signal/unicore32: Generate siginfo in ucs32_notify_die
signal/unicore32: Use send_sig_fault where appropriate
signal/arc: Use force_sig_fault where appropriate
signal/arc: Push siginfo generation into unhandled_exception
signal/ia64: Use force_sig_fault where appropriate
signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
signal/ia64: Use the generic force_sigsegv in setup_frame
signal/arm/kvm: Use send_sig_mceerr
signal/arm: Use send_sig_fault where appropriate
signal/arm: Use force_sig_fault where appropriate
...
lockdep_assert_held() is better suited to checking locking requirements,
since it won't get confused when someone else holds the lock. This is
also a step towards possibly removing spin_is_locked().
Signed-off-by: Lance Roy <ldr709@gmail.com>
Cc: Cliff Whickman <cpw@sgi.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Robin Holt <robinmholt@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The EEPROMs which hold the SPD data on DDR4 memory modules are no
longer standard AT24C02-compatible EEPROMs. They are 512-byte EEPROMs
which use only 1 I2C address for data access. You need to switch
between the lower page and the upper page of data by sending commands
on the SMBus.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/misc/eeprom/at25.c: In function 'at25_remove':
drivers/misc/eeprom/at25.c:384:20: warning:
variable 'at25' set but not used [-Wunused-but-set-variable]
Since commit 96d08fb43e ("eeprom: at25: use devm_nvmem_register()"),
at25_remove is do nothing, so can be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/misc/mic/scif/scif_dma.c: In function 'scif_rma_list_dma_copy_wrapper':
drivers/misc/mic/scif/scif_dma.c:1558:27: warning:
variable 'dst_dma_addr' set but not used [-Wunused-but-set-variable]
drivers/misc/mic/scif/scif_dma.c:1558:13: warning:
variable 'src_dma_addr' set but not used [-Wunused-but-set-variable]
They never used since introduction in
commit 7cc31cd277 ("misc: mic: SCIF DMA and CPU copy interface")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In _scif_prog_signal(), the boolean variable 'x100' is used to indicate
whether the MIC Coprocessor is X100. If 'x100' is true, the status
descriptor will be used to write the value to the destination. Otherwise, a
DMA pool will be allocated for this purpose. Specifically, if the DMA pool
is allocated successfully, two memory addresses will be returned. One is
for the CPU and the other is for the device to access the DMA pool. The
former is stored to the variable 'status' and the latter is stored to the
variable 'src'. After the allocation, the address in 'src' is saved to
'status->src_dma_addr', which is actually in the DMA pool, and 'src' is
then modified.
Later on, if an error occurs, the execution flow will transfer to the label
'dma_fail', which will check 'x100' and free up the allocated DMA pool if
'x100' is false. The point here is that 'status->src_dma_addr' is used for
freeing up the DMA pool. As mentioned before, 'status->src_dma_addr' is in
the DMA pool. And thus, the device is able to modify this data. This can
potentially cause failures when freeing up the DMA pool because of the
modified device address.
This patch avoids the above issue by using the variable 'src' (with
necessary calculation) to free up the DMA pool.
Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is not safe to dereference an object before a null test. It is
not needed and just remove them. Ftrace can be used instead.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The check for ret < 0 is redundant as any places prior to this point
where ret is set to an error value the code will exit out of the loop
to the error exit label 'err'. Remove this redundant dead code.
Detected by CoverityScan, CID#1339528 ("Logically dead code")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/misc/vmw_vmci/vmci_host.c: In function 'vmci_host_do_alloc_queuepair':
drivers/misc/vmw_vmci/vmci_host.c:450:6: warning:
variable 'cid' set but not used [-Wunused-but-set-variable]
u32 cid;
^
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Looks like during merging the bulk POLL* -> EPOLL* replacement
missed the patch
'commit af336cabe0 ("mei: limit the number of queued writes")'
Fix sparse warning:
drivers/misc/mei/main.c:602:13: warning: restricted __poll_t degrades to integer
drivers/misc/mei/main.c:605:30: warning: invalid assignment: |=
drivers/misc/mei/main.c:605:30: left side has type restricted __poll_t
drivers/misc/mei/main.c:605:30: right side has type int
Fixes: af336cabe0 ("mei: limit the number of queued writes")
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When adding a VMCI resource, the check for an existing entry
would ignore that the new entry could be a wildcard. This could
result in multiple resource entries that would match a given
handle. One disastrous outcome of this is that the
refcounting used to ensure that delayed callbacks for VMCI
datagrams have run before the datagram is destroyed can be
wrong, since the refcount could be increased on the duplicate
entry. This in turn leads to a use after free bug. This issue
was discovered by Hangbin Liu using KASAN and syzkaller.
Fixes: bc63dedb7d ("VMCI: resource object implementation")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function should return -EFAULT when copy_from_user fails. Even
though the caller does not distinguish them. but we should keep backward
compatibility.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clang warns when a variable is assigned to itself.
drivers/misc/mic/scif/scif_dma.c:1577:12: warning: explicitly assigning
value of variable of type 'bool' (aka '_Bool') to itself [-Wself-assign]
dst_local = dst_local;
~~~~~~~~~ ^ ~~~~~~~~~
1 warning generated.
This is usually done to avoid an unused variable warning, which is the
case here. dst_local is used nowhere in this function, which has been
the case since the initial code drop in commit 7cc31cd277 ("misc: mic:
SCIF DMA and CPU copy interface") in 2015. Just remove the variable, it
can be added back if it was intended to be used.
Link: https://github.com/ClangBuiltLinux/linux/issues/107
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
module.h already contains moduleparam.h, so it is safe to remove
the redundant include.
The issue is detected with the help of Coccinelle.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kgdbts current fails when compiled with restrict:
drivers/misc/kgdbts.c: In function ‘configure_kgdbts’:
drivers/misc/kgdbts.c:1070:2: error: ‘strcpy’ source argument is the same as destination [-Werror=restrict]
strcpy(config, opt);
^~~~~~~~~~~~~~~~~~~
As the error says, config is being used in both the source and destination.
Refactor the code to avoid the extra copy and put the parsing closer to
the actual location.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clang warns when multiple pairs of parentheses are used for a single
conditional statement.
drivers/misc/echo/echo.c:384:27: warning: equality comparison with
extraneous parentheses [-Wparentheses-equality]
if ((ec->nonupdate_dwell == 0)) {
~~~~~~~~~~~~~~~~~~~~^~~~
drivers/misc/echo/echo.c:384:27: note: remove extraneous parentheses
around the comparison to silence this warning
if ((ec->nonupdate_dwell == 0)) {
~ ^ ~
drivers/misc/echo/echo.c:384:27: note: use '=' to turn this equality
comparison into an assignment
if ((ec->nonupdate_dwell == 0)) {
^~
=
1 warning generated.
Remove them and while we're at it, simplify the zero check as '!var' is
used more than 'var == 0'.
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
of_node_put has taken the null pinter check into account. So it is
safe to remove the duplicated check before of_node_put.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is useful to expose how many times the balloon resets. If it happens
more than very rarely - this is an indication for a problem.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change all the remaining return values to int to avoid mistakes. Reduce
indentation when possible.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In preparation for supporting compaction and OOM notification, this
patch reworks the inflate/deflate loops. The main idea is to separate
the allocation, communication with the hypervisor, and the handling of
errors from each other. Doing will allow us to perform concurrent
inflation and deflation, excluding the actual communication with the
hypervisor.
To do so, we need to get rid of the remaining global state that is kept
in the balloon struct, specifically the refuse_list. When the VM
communicates with the hypervisor, it does not free or put back pages
to the balloon list and instead only moves the pages whose status
indicated failure into a refuse_list on the stack. Once the operation
completes, the inflation or deflation functions handle the list
appropriately.
As we do that, we can consolidate the communication with the hypervisor
for both the lock and unlock operations into a single function. We also
reuse the deflation function for popping the balloon.
As a preparation for preventing races, we hold a spinlock when the
communication actually takes place, and use atomic operations for
updating the balloon size. The balloon page list is still racy and will
be handled in the next patch.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To allow the balloon statistics to be updated concurrently, we change
the statistics to be held per core and aggregate it when needed.
To avoid the memory overhead of keeping the statistics per core, and
since it is likely not used by most users, we start updating the
statistics only after the first use. A read-write semaphore is used to
protect the statistics initialization and avoid races. This semaphore is
(and will) be used to protect configuration changes during reset.
While we are at it, address some other issues: change the statistics
update to inline functions instead of define; use ulong for saving the
statistics; and clean the statistics printouts.
Note that this patch changes the format of the outputs. If there are any
automatic tools that use the statistics, they might fail.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As we want to leave as little as possible on the global balloon
structure, to avoid possible future races, we want to get rid sysinfo.
We can actually get the total_ram directly, and simplify the logic of
vmballoon_send_get_target() a little.
While we are doing that, let's return int and avoid mistakes due to
bool/int conversions.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The required change in the balloon size is currently computed in
vmballoon_work(), vmballoon_inflate() and vmballoon_deflate(). Refactor
it to simplify the next patches.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The name of the macro'd VMW_BALLOON_2M_SHIFT is misleading. The value
reflects 2M huge-page order. Unfortunately, we cannot use
HPAGE_PMD_ORDER, since it is not defined when transparent huge-pages are
off, so we need to define our own one.
Rename it to VMW_BALLOON_2M_ORDER. No functional change.
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, when the hypervisor rejects a page during lock operation, the
VM treats pages differently according to the error-code: in certain
cases the page is immediately freed, and in others it is put on a
rejection list and only freed later.
The behavior does not make too much sense. If the page is freed
immediately it is very likely to be used again in the next batch of
allocations, and be rejected again.
In addition, for support of compaction and OOM notifiers, we wish to
separate the logic that communicates with the hypervisor (as well as
analyzes the status of each page) from the logic that allocates or free
pages.
Treat all errors the same way, queuing the pages on the refuse list.
Move to the next allocation size (4k) when too many pages are refused.
Free the refused pages when moving to the next size to avoid situations
in which too much memory is waiting to be freed on the refused list.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current abstractions for batch vs single operations seem suboptimal
and complicate the implementation of additional features (OOM,
compaction).
The immediate problem of the current abstractions is that they cause
differences in how operations are handled when batching is on or off.
For example, the refused_alloc counter is not updated when batching is
on. These discrepancies are caused by code redundancies.
Instead, this patch presents three type of operations, according to
whether batching is on or off: (1) add page, (2) communication with the
hypervisor and (3) retrieving the status of a page.
To avoid the overhead of virtual functions, and since we do not expect
additional interfaces for communication with the hypervisor, we use
static keys instead of virtual functions.
Finally, while we are at it, change vmballoon_init_batching() to return
int instead of bool, to be consistent in the return type and avoid
potential coding errors.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Splitting the allocations between sleeping and non-sleeping made some
sort of sense as long as rate-limiting was enabled. Now that it is
removed, we need to decide - either we want sleeping allocations or not.
Since no other Linux balloon driver (hv, Xen, virtio) uses sleeping
allocations, use the same approach.
We do distinguish, however, between 2MB allocations and 4kB allocations
and prevent reclamation on 2MB. In both cases, we avoid using emergency
low-memory pools, as it may cause undesired effects.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The use of accessors for batch entries complicates the code and makes it
less readable. Remove it an instead use bit-fields.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The lock and unlock code paths are very similar, so avoid the duplicate
code by merging them together.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that we have a single point, unify the tracing and collecting the
statistics for commands and their failure. While it might somewhat
reduce the control over debugging, it cleans the code a lot.
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By inlining the hypercall interface, we can unify several operations
into one central point in the code:
- Updating the target.
- Updating when a reset is needed.
- Update statistics (which will be done later in the patch-set).
- Print debug-messages (although they cannot be enabled as selectively).
Reviewed-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace "fallthru" with a proper "fall through" annotation.
This fix is part of the ongoing efforts to enabling
-Wimplicit-fallthrough
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Dimitri Sivanich <sivanich@hpe.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The AFU Information DVSEC capability is a means to extract common,
general information about all of the AFUs associated with a Function
independent of the specific functionality that each AFU provides.
Write in the AFU Index field allows to access to the descriptor data
for each AFU.
With the current code, we are not able to access to these specific data
when the index >= 1 because we are writing to the wrong location.
All requests to the data of each AFU are pointing to those of the AFU 0,
which could have impacts when using a card with more than one AFU per
function.
This patch fixes the access to the AFU Descriptor Data indexed by the
AFU Info Index field.
Fixes: 5ef3166e8a ("ocxl: Driver code for 'generic' opencapi devices")
Cc: stable <stable@vger.kernel.org> # 4.16
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The genweq_add_file and genwqe_del_file by caching current without
using reference counting embed the assumption that a file descriptor
will never be passed from one process to another. It even embeds the
assumption that the the thread that opened the file will be in
existence when the process terminates. Neither of which are
guaranteed to be true.
Therefore replace caching the task_struct of the opener with
pid of the openers thread group id. All the knowledge of the
opener is used for is as the target of SIGKILL and a SIGKILL
will kill the entire process group.
Rename genwqe_force_sig to genwqe_terminate, remove it's unncessary
signal argument, update it's ownly caller, and use kill_pid
instead of force_sig.
The work force_sig does in changing signal handling state is not
relevant to SIGKILL sent as SEND_SIG_PRIV. The exact same processess
will be killed just with less work, and less confusion. The work done
by force_sig is really only needed for handling syncrhonous
exceptions.
It will still be possible to cause genwqe_device_remove to wait
8 seconds by passing a file descriptor to another process but
the possible user after free is fixed.
Fixes: eaf4722d46 ("GenWQE Character device and DDCB queue")
Cc: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Frank Haverkamp <haver@linux.vnet.ibm.com>
Cc: Joerg-Stephan Vogt <jsvogt@de.ibm.com>
Cc: Michael Jung <mijung@gmx.net>
Cc: Michael Ruettger <michael@ibmra.de>
Cc: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Eberhard S. Amann <esa@linux.vnet.ibm.com>
Cc: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Cc: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
kfree has taken null pointer into account. so check the null pointer
before kfree is meaningless.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Acked-by: Robin Holt <robinmholt@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.
Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Resolved "ERROR: do not initialise statics to 0"
Signed-off-by: Parth Y Shah <sparth1292@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Array prox_curr_ma is declared but never used, hence it is redundant
and can be removed.
Cleans up clang warning:
warning: 'prox_curr_ma' defined but not used [-Wunused-const-variable=]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Array ir_currents is declared but never used, hence it is redundant
and can be removed.
Cleans up clang warning:
warning: 'ir_currents' defined but not used [-Wunused-const-variable=]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
val is indirectly controlled by user-space, hence leading to a
potential exploitation of the Spectre variant 1 vulnerability.
This issue was detected with the help of Smatch:
drivers/misc/hmc6352.c:54 compass_store() warn: potential spectre issue
'map' [r]
Fix this by sanitizing val before using it to index map
Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].
[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the assignment is flipped and rc is always 0.
Signed-off-by: Bryant G. Ly <bryantly@linux.ibm.com>
Fixes: 0eca353e7a ("misc: IBM Virtual Management Channel Driver (VMC)")
Reviewed-by: Bradley Warrum <bwarrum@us.ibm.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
