Add regs_get_kernel_argument() which returns Nth argument of a
function call.
This enables ftrace kprobe events to access kernel function arguments
via $argN syntax.
This is the s390 variant of commit a823c35ff2 ("arm64: ptrace: Add
function argument access API").
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This is the s390 variant of commit 9855c4626c ("selftests/ftrace:
Add ppc support for kprobe args tests").
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
ftrace_regs_caller is an alias to ftrace_caller - making ftrace_caller
quite heavyweight. Split the function and provide an ftrace_caller
implementation which comes with fewer instructions. Especially getting
rid of 'stosm' on each function entry should help here, e.g. to
have less performance impact on live patched functions.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Add ftrace_instruction_pointer_set() helper function to match x86.
See commit 2860cd8a23 ("livepatch: Use the default ftrace_ops
instead of REGS when ARGS is available").
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Add HAVE_DYNAMIC_FTRACE_WITH_ARGS support similar to commit 02a474ca26
("ftrace/x86: Allow for arguments to be passed in to ftrace_regs by default").
s390's ftrace implementation always provides all registers with
pt_regs, therefore this is trivial.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Trivial patch just to get rid of the leading underscores.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Specify HAVE_JUMP_LABEL_BATCH in header file. This allows to make use
of the arch_jump_label_transform_queue()/arch_jump_label_transform_apply()
mechanism.
However unlike on x86, which currently is the only user of this
mechanism, the to be patched instructions are still directly
modified. The only difference to before is that serialization is only
done after all instructions have been modified. This way the number of
serialization/synchronization events is reduced.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
CPUs must be serialized also when ftrace_graph_caller gets patched.
This is missing since ftrace function graph support was added on s390.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Introduce a text_poke_sync() similar to what x86 has. This can be
used to execute a serializing instruction on all CPUs (including
the current one).
Note: according to the Principles of Operation an IPI (= interrupt)
will already serialize a CPU, however it is better to be explicit. In
addition on_each_cpu() makes sure that also the current CPU get
serialized - just to make sure that possible preemption can prevent
some theoretical case where a CPU will not be serialized.
Therefore text_poke_sync() has to be used whenever code got modified,
just to avoid to rely on implicit serialization.
Also introduce text_poke_sync_lock() which will also disable CPU
hotplug, to prevent that any CPU is just going online with a
prefetched old version of a modified instruction.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Factor out bcr_serialize() inline assembly function which describes
what the bcr instruction is used for.
Use bcr_serialize() like before in mb(), but also in upcoming changes.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Modified stack unwinder self tests to use kunit framework. The
functionality stayed the same but the output format is now in tap13
format.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Mete Durlu <meted@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The memory for amode31 section is allocated from the decompressed
kernel. Instead, allocate that memory from the decompressor. This
is a prerequisite to allow initialization of the virtual memory
before the decompressed kernel takes over.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Partially revert commit 4555b9f34296 ("s390/boot: move
dma sections from decompressor to decompressed kernel").
This is a prerequisite to allow initialization of virtual
memory in decompressor and avoid overwriting of ASCEs in
the decompressed kernel otherwise.
Since the control registers 2, 5 and 15 are reinitialized
in the decompressed kernel again, this change does not
prevent relocating of amode31 section in any way.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Add a few testcases to make sure that it's not possible to place
a kprobe in the mid of an instruction on s390.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
FTRACE_GEN_NOP_ASM(name) can be used to generate assembly functions with
the required information added to allow tracing via kprobes/ftrace. It
adds the nop instruction which will be patched by ftrace later. If the
compiler supports -mnop-mcount it will also add an entry to the
__mcount_loc section.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Fix these warnings that are reported when compiling with W=1:
drivers/s390/char/sclp_sd.c:132: warning: Function parameter or member 'listener' not described in 'sclp_sd_listener_init'
drivers/s390/char/sclp_sd.c:408: warning: Function parameter or member 'cookie' not described in 'sclp_sd_file_update_async'
drivers/s390/char/sclp_sd.c:422: warning: Function parameter or member 'attr' not described in 'reload_store'
drivers/s390/char/sclp_sd.c:422: warning: Function parameter or member 'buf' not described in 'reload_store'
drivers/s390/char/sclp_sd.c:422: warning: Function parameter or member 'count' not described in 'reload_store'
drivers/s390/char/sclp_sd.c:457: warning: Function parameter or member 'file' not described in 'data_read'
drivers/s390/char/sclp_sd.c:457: warning: Function parameter or member 'attr' not described in 'data_read'
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
cdev->online for the purge function must not be checked for the
non-IO subchannel type. Make sure that we are deriving the cdev only
from sch-type SUBCHANNEL_TYPE_IO.
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
We often need to figure out what operations were performed in response
to an error or availability event. The operations are easily accessible
in s390dbf/pci_msg but the events have to be correlated with these from
either the kernel log or s390dbf/pci_err. Improve this situation by
logging the most important data from error and availability events that
is the FID, PEC and FH together with the operations.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The cio_ignore list is used to create and maintain the list of devices
which is to be ignored by Linux. During boot-time, this list is adjusted
and accommodate all the devices which are configured on the HMC
interface. Once these devices are accessible, they are then available to
Linux and set online.
cio_ignore purge function should align with this functionality. But
currently, the subchannel associated with the offline-devices are not
unregistered during purge. Add an explicit subchannel-unregister function
in the purge_fn callback.
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Since commit 8256adda1f ("s390/pci: handle FH state mismatch only on
disable") zpci_disable_device() returns -EINVAL when the platform
detects an attempt to disable a PCI function that it sees as already
disabled.
In most situations we want to abort whenever this happens and abort is
possible since it either means that the device vanished but we haven't
gotten an availability event yet, or the FH got out of sync which should
not happen.
Unfortunately there is an inconsistency between the LPAR and z/VM
hypervisors on whether error events for PCI functions contain an
an enabled or a general handle. So under z/VM it can happen that our
most up to date function handle is enabled but trying to disable the
function results in the aforementioned error.
Since recover is designed to be used to recover functions from the error
state let's make it robust to this inconsistency by explicitly treating
it as a successful disable.
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Check whether the specified address points to the start of an
instruction to prevent users from setting a kprobe in the mid of
an instruction which would crash the kernel.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
ftrace_shared_hotpatch_trampoline() never returns NULL,
therefore quite a bit of code can be removed.
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
In commit b212921b13 ("elf: don't use MAP_FIXED_NOREPLACE for elf
executable mappings") we still leave MAP_FIXED_NOREPLACE in place for
load_elf_interp.
Unfortunately, this will cause kernel to fail to start with:
1 (init): Uhuuh, elf segment at 00003ffff7ffd000 requested but the memory is mapped already
Failed to execute /init (error -17)
The reason is that the elf interpreter (ld.so) has overlapping segments.
readelf -l ld-2.31.so
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000
0x000000000002c94c 0x000000000002c94c R E 0x10000
LOAD 0x000000000002dae0 0x000000000003dae0 0x000000000003dae0
0x00000000000021e8 0x0000000000002320 RW 0x10000
LOAD 0x000000000002fe00 0x000000000003fe00 0x000000000003fe00
0x00000000000011ac 0x0000000000001328 RW 0x10000
The reason for this problem is the same as described in commit
ad55eac74f ("elf: enforce MAP_FIXED on overlaying elf segments").
Not only executable binaries, elf interpreters (e.g. ld.so) can have
overlapping elf segments, so we better drop MAP_FIXED_NOREPLACE and go
back to MAP_FIXED in load_elf_interp.
Fixes: 4ed2863951 ("fs, elf: drop MAP_FIXED usage from elf_map")
Cc: <stable@vger.kernel.org> # v4.19
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Chen Jingwen <chenjingwen6@huawei.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull ext4 fixes from Ted Ts'o:
"Fix a number of ext4 bugs in fast_commit, inline data, and delayed
allocation.
Also fix error handling code paths in ext4_dx_readdir() and
ext4_fill_super().
Finally, avoid a grabbing a journal head in the delayed allocation
write in the common cases where we are overwriting a pre-existing
block or appending to an inode"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: recheck buffer uptodate bit under buffer lock
ext4: fix potential infinite loop in ext4_dx_readdir()
ext4: flush s_error_work before journal destroy in ext4_fill_super
ext4: fix loff_t overflow in ext4_max_bitmap_size()
ext4: fix reserved space counter leakage
ext4: limit the number of blocks in one ADD_RANGE TLV
ext4: enforce buffer head state assertion in ext4_da_map_blocks
ext4: remove extent cache entries when truncating inline data
ext4: drop unnecessary journal handle in delalloc write
ext4: factor out write end code of inline file
ext4: correct the error path of ext4_write_inline_data_end()
ext4: check and update i_disksize properly
ext4: add error checking to ext4_ext_replay_set_iblocks()
The objtool warning that the kvm instruction emulation code triggered
wasn't very useful:
arch/x86/kvm/emulate.o: warning: objtool: __ex_table+0x4: don't know how to handle reloc symbol type: kvm_fastop_exception
in that it helpfully tells you which symbol name it had trouble figuring
out the relocation for, but it doesn't actually say what the unknown
symbol type was that triggered it all.
In this case it was because of missing type information (type 0, aka
STT_NOTYPE), but on the whole it really should just have printed that
out as part of the message.
Because if this warning triggers, that's very much the first thing you
want to know - why did reloc2sec_off() return failure for that symbol?
So rather than just saying you can't handle some type of symbol without
saying what the type _was_, just print out the type number too.
Fixes: 24ff652573 ("objtool: Teach get_alt_entry() about more relocation types")
Link: https://lore.kernel.org/lkml/CAHk-=wiZwq-0LknKhXN4M+T8jbxn_2i9mcKpO+OaBSSq_Eh7tg@mail.gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The recent change to make objtool aware of more symbol relocation types
(commit 24ff652573: "objtool: Teach get_alt_entry() about more
relocation types") also added another check, and resulted in this
objtool warning when building kvm on x86:
arch/x86/kvm/emulate.o: warning: objtool: __ex_table+0x4: don't know how to handle reloc symbol type: kvm_fastop_exception
The reason seems to be that kvm_fastop_exception() is marked as a global
symbol, which causes the relocation to ke kept around for objtool. And
at the same time, the kvm_fastop_exception definition (which is done as
an inline asm statement) doesn't actually set the type of the global,
which then makes objtool unhappy.
The minimal fix is to just not mark kvm_fastop_exception as being a
global symbol. It's only used in that one compilation unit anyway, so
it was always pointless. That's how all the other local exception table
labels are done.
I'm not entirely happy about the kinds of games that the kvm code plays
with doing its own exception handling, and the fact that it confused
objtool is most definitely a symptom of the code being a bit too subtle
and ad-hoc. But at least this trivial one-liner makes objtool no longer
upset about what is going on.
Fixes: 24ff652573 ("objtool: Teach get_alt_entry() about more relocation types")
Link: https://lore.kernel.org/lkml/CAHk-=wiZwq-0LknKhXN4M+T8jbxn_2i9mcKpO+OaBSSq_Eh7tg@mail.gmail.com/
Cc: Borislav Petkov <bp@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull char/misc driver fixes from Greg KH:
"Here are some small misc driver fixes for 5.15-rc4. They are in two
"groups":
- ipack driver fixes for issues found by Johan Hovold
- interconnect driver fixes for reported problems
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
ipack: ipoctal: fix module reference leak
ipack: ipoctal: fix missing allocation-failure check
ipack: ipoctal: fix tty-registration error handling
ipack: ipoctal: fix tty registration race
ipack: ipoctal: fix stack information leak
interconnect: qcom: sdm660: Add missing a2noc qos clocks
dt-bindings: interconnect: sdm660: Add missing a2noc qos clocks
interconnect: qcom: sdm660: Correct NOC_QOS_PRIORITY shift and mask
interconnect: qcom: sdm660: Fix id of slv_cnoc_mnoc_cfg
Pull driver core fixes from Greg KH:
"Here are some driver core and kernfs fixes for reported issues for
5.15-rc4. These fixes include:
- kernfs positive dentry bugfix
- debugfs_create_file_size error path fix
- cpumask sysfs file bugfix to preserve the user/kernel abi (has been
reported multiple times.)
- devlink fixes for mdiobus devices as reported by the subsystem
maintainers.
Also included in here are some devlink debugging changes to make it
easier for people to report problems when asked. They have already
helped with the mdiobus and other subsystems reporting issues.
All of these have been linux-next for a while with no reported issues"
* tag 'driver-core-5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
kernfs: also call kernfs_set_rev() for positive dentry
driver core: Add debug logs when fwnode links are added/deleted
driver core: Create __fwnode_link_del() helper function
driver core: Set deferred probe reason when deferred by driver core
net: mdiobus: Set FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD for mdiobus parents
driver core: fw_devlink: Add support for FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD
driver core: fw_devlink: Improve handling of cyclic dependencies
cpumask: Omit terminating null byte in cpumap_print_{list,bitmask}_to_buf
debugfs: debugfs_create_file_size(): use IS_ERR to check for error
Pull scheduler fixes from Borislav Petkov:
- Tell the compiler to always inline is_percpu_thread()
- Make sure tunable_scaling buffer is null-terminated after an update
in sysfs
- Fix LTP named regression due to cgroup list ordering
* tag 'sched_urgent_for_v5.15_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Always inline is_percpu_thread()
sched/fair: Null terminate buffer when updating tunable_scaling
sched/fair: Add ancestors of unthrottled undecayed cfs_rq
Pull perf fixes from Borislav Petkov:
- Make sure the destroy callback is reset when a event initialization
fails
- Update the event constraints for Icelake
- Make sure the active time of an event is updated even for inactive
events
* tag 'perf_urgent_for_v5.15_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: fix userpage->time_enabled of inactive events
perf/x86/intel: Update event constraints for ICX
perf/x86: Reset destroy callback on event init failure
Pull objtool fix from Borislav Petkov:
- Handle symbol relocations properly due to changes in the toolchains
which remove section symbols now
* tag 'objtool_urgent_for_v5.15_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Teach get_alt_entry() about more relocation types
Pull hwmon fixes from Guenter Roeck:
- Fixed various potential NULL pointer accesses in w8379* drivers
- Improved error handling, fault reporting, and fixed rounding in
thmp421 driver
- Fixed error handling in ltc2947 driver
- Added missing attribute to pmbus/mp2975 driver
- Fixed attribute values in pbus/ibm-cffps, occ, and mlxreg-fan
drivers
- Removed unused residual code from k10temp driver
* tag 'hwmon-for-v5.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (w83793) Fix NULL pointer dereference by removing unnecessary structure field
hwmon: (w83792d) Fix NULL pointer dereference by removing unnecessary structure field
hwmon: (w83791d) Fix NULL pointer dereference by removing unnecessary structure field
hwmon: (pmbus/mp2975) Add missed POUT attribute for page 1 mp2975 controller
hwmon: (pmbus/ibm-cffps) max_power_out swap changes
hwmon: (occ) Fix P10 VRM temp sensors
hwmon: (ltc2947) Properly handle errors when looking for the external clock
hwmon: (tmp421) fix rounding for negative values
hwmon: (tmp421) report /PVLD condition as fault
hwmon: (tmp421) handle I2C errors
hwmon: (mlxreg-fan) Return non-zero value when fan current state is enforced from sysfs
hwmon: (k10temp) Remove residues of current and voltage
Pull ksmbd server fixes from Steve French:
"Eleven fixes for the ksmbd kernel server, mostly security related:
- an important fix for disabling weak NTLMv1 authentication
- seven security (improved buffer overflow checks) fixes
- fix for wrong infolevel struct used in some getattr/setattr paths
- two small documentation fixes"
* tag '5.15-rc3-ksmbd-fixes' of git://git.samba.org/ksmbd:
ksmbd: missing check for NULL in convert_to_nt_pathname()
ksmbd: fix transform header validation
ksmbd: add buffer validation for SMB2_CREATE_CONTEXT
ksmbd: add validation in smb2 negotiate
ksmbd: add request buffer validation in smb2_set_info
ksmbd: use correct basic info level in set_file_basic_info()
ksmbd: remove NTLMv1 authentication
ksmbd: fix documentation for 2 functions
MAINTAINERS: rename cifs_common to smbfs_common in cifs and ksmbd entry
ksmbd: fix invalid request buffer access in compound
ksmbd: remove RFC1002 check in smb2 request
Pull SCSI fixes from James Bottomley:
"Five fairly minor fixes and spelling updates, all in drivers. Even
though the ufs fix is in tracing, it's a potentially exploitable use
beyond end of array bug"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: csiostor: Add module softdep on cxgb4
scsi: qla2xxx: Fix excessive messages during device logout
scsi: virtio_scsi: Fix spelling mistake "Unsupport" -> "Unsupported"
scsi: ses: Fix unsigned comparison with less than zero
scsi: ufs: Fix illegal offset in UPIU event trace
Pull block fixes from Jens Axboe:
"A few block fixes for this release:
- Revert a BFQ commit that causes breakage for people. Unfortunately
it was auto-selected for stable as well, so now 5.14.7 suffers from
it too. Hopefully stable will pick up this revert quickly too, so
we can remove the issue on that end as well.
- Add a quirk for Apple NVMe controllers, which due to their
non-compliance broke due to the introduction of command sequences
(Keith)
- Use shifts in nbd, fixing a __divdi3 issue (Nick)"
* tag 'block-5.15-2021-10-01' of git://git.kernel.dk/linux-block:
nbd: use shifts rather than multiplies
Revert "block, bfq: honor already-setup queue merges"
nvme: add command id quirk for apple controllers
