In preparation for merging the per CPU buffers into one buffer when
we retrieve the pstore ftrace data, we store the timestamp as a
counter in the ftrace pstore record. We store the CPU number as well
if !PSTORE_CPU_IN_IP, in this case we shift the counter and may lose
ordering there but we preserve the same record size. The timestamp counter
is also racy, and not doing any locking or synchronization here results
in the benefit of lower overhead. Since we don't care much here for exact
ordering of function traces across CPUs, we don't synchronize and may lose
some counter updates but I'm ok with that.
Using trace_clock() results in much lower performance so avoid using it
since we don't want accuracy in timestamp and need a rough ordering to
perform merge.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: updated commit message, added comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split
the ftrace space into multiple zones depending on the number of CPUs.
This speeds up the performance of function tracing by about 280% in my
tests as we avoid the locking. The trade off being lesser space available
per CPU. Let the ramoops user decide which option they want based on pdata
flag.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: added max_ftrace_cnt to track size, added DT logic and docs]
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently ramoops_init_przs() is hard wired only for panic dump zone
array. In preparation for the ftrace zone array (one zone per-cpu) and pmsg
zone array, make the function more generic to be able to handle this case.
Heavily based on similar work from Joel Fernandes.
Signed-off-by: Kees Cook <keescook@chromium.org>
In preparation of not locking at all for certain buffers depending on if
there's contention, make locking optional depending on the initialization
of the prz.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: moved locking flag into prz instead of via caller arguments]
Signed-off-by: Kees Cook <keescook@chromium.org>
Currently pstore has a global spinlock for all zones. Since the zones
are independent and modify different areas of memory, there's no need
to have a global lock, so we should use a per-zone lock as introduced
here. Also, when ramoops's ftrace use-case has a FTRACE_PER_CPU flag
introduced later, which splits the ftrace memory area into a single zone
per CPU, it will eliminate the need for locking. In preparation for this,
make the locking optional.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: updated commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
Pull UBI[FS] fixes from Richard Weinberger:
"This contains fixes for issues in both UBI and UBIFS:
- Fallout from the merge window, refactoring UBI code introduced some
issues.
- Fixes for an UBIFS readdir bug which can cause getdents() to busy
loop for ever and a bug in the UBIFS xattr code"
* tag 'upstream-4.9-rc2' of git://git.infradead.org/linux-ubifs:
ubifs: Abort readdir upon error
UBI: Fix crash in try_recover_peb()
ubi: fix swapped arguments to call to ubi_alloc_aeb
ubifs: Fix xattr_names length in exit paths
ubifs: Rename ubifs_rename2
Pull ext4 fixes from Ted Ts'o:
"A few bug fixes and add some missing KERN_CONT annotations"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: add missing KERN_CONT to a few more debugging uses
fscrypto: lock inode while setting encryption policy
ext4: correct endianness conversion in __xattr_check_inode()
fscrypto: make XTS tweak initialization endian-independent
ext4: do not advertise encryption support when disabled
jbd2: fix incorrect unlock on j_list_lock
ext4: super.c: Update logging style using KERN_CONT
Pull SCSI target fixes from Nicholas Bellinger:
"Here are the outstanding target-pending fixes for v4.9-rc2.
This includes:
- Fix v4.1.y+ reference leak regression with concurrent TMR
ABORT_TASK + session shutdown. (Vaibhav Tandon)
- Enable tcm_fc w/ SCF_USE_CPUID to avoid host exchange timeouts
(Hannes)
- target/user error sense handling fixes. (Andy + MNC + HCH)
- Fix iscsi-target NOP_OUT error path iscsi_cmd descriptor leak
(Varun)
- Two EXTENDED_COPY SCSI status fixes for ESX VAAI (Dinesh Israni +
Nixon Vincent)
- Revert a v4.8 residual overflow change, that breaks sg_inq with
small allocation lengths.
There are a number of folks stress testing the v4.1.y regression fix
in their environments, and more folks doing iser-target I/O stress
testing atop recent v4.x.y code.
There is also one v4.2.y+ RCU conversion regression related to
explicit NodeACL configfs changes, that is still being tracked down"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
target/tcm_fc: use CPU affinity for responses
target/tcm_fc: Update debugging statements to match libfc usage
target/tcm_fc: return detailed error in ft_sess_create()
target/tcm_fc: print command pointer in debug message
target: fix potential race window in target_sess_cmd_list_waiting()
Revert "target: Fix residual overflow handling in target_complete_cmd_with_length"
target: Don't override EXTENDED_COPY xcopy_pt_cmd SCSI status code
target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLE
target: Re-add missing SCF_ACK_KREF assignment in v4.1.y
iscsi-target: fix iscsi cmd leak
iscsi-target: fix spelling mistake "Unsolicitied" -> "Unsolicited"
target/user: Fix comments to not refer to data ring
target/user: Return an error if cmd data size is too large
target/user: Use sense_reason_t in tcmu_queue_cmd_ring
Pull hwmon fixes from Guenter Roeck:
"Couple of hwmon fixes:
Fix a potential ERR_PTR dereference in max31790 driver, and handle
temperature readings below 0 in adm9240 driver"
* tag 'hwmon-for-linus-v4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (max31790) potential ERR_PTR dereference
hwmon: (adm9240) handle temperature readings below 0
Pull IPMI updates from Corey Minyard:
"A small bug fix and a new driver for acting as an IPMI device.
I was on vacation during the merge window (a long vacation) but this
is a bug fix that should go in and a new driver that shouldn't hurt
anything.
This has been in linux-next for a month or so"
* tag 'for-linus-4.9-2' of git://git.code.sf.net/p/openipmi/linux-ipmi:
ipmi: fix crash on reading version from proc after unregisted bmc
ipmi/bt-bmc: remove redundant return value check of platform_get_resource()
ipmi/bt-bmc: add a dependency on ARCH_ASPEED
ipmi: Fix ioremap error handling in bt-bmc
ipmi: add an Aspeed BT IPMI BMC driver
Pull timer updates from Thomas Gleixner:
"This updates contains:
- A revert which addresses a boot failure on ARM Sun5i platforms
- A new clocksource driver, which has been delayed beyond rc1 due to
an interrupt driver issue which was unearthed by this driver. The
debugging of that issue and the discussion about the proper
solution made this driver miss the merge window. There is no point
in delaying it for a full cycle as it completes the basic mainline
support for the new JCore platform and does not create any risk
outside of that platform"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init"
clocksource: Add J-Core timer/clocksource driver
of: Add J-Core timer bindings
Pull x86 fixes from Ingo Molnar:
"Three fixes, a hw-enablement and a cross-arch fix/enablement change:
- SGI/UV fix for older platforms
- x32 signal handling fix
- older x86 platform bootup APIC fix
- AVX512-4VNNIW (Neural Network Instructions) and AVX512-4FMAPS
(Multiply Accumulation Single precision instructions) enablement.
- move thread_info back into x86 specific code, to make life easier
for other architectures trying to make use of
CONFIG_THREAD_INFO_IN_TASK_STRUCT=y"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot/smp: Don't try to poke disabled/non-existent APIC
sched/core, x86: Make struct thread_info arch specific again
x86/signal: Remove bogus user_64bit_mode() check from sigaction_compat_abi()
x86/platform/UV: Fix support for EFI_OLD_MEMMAP after BIOS callback updates
x86/cpufeature: Add AVX512_4VNNIW and AVX512_4FMAPS features
x86/vmware: Skip timer_irq_works() check on VMware
Pull vmap stack fixes from Ingo Molnar:
"This is fallout from CONFIG_HAVE_ARCH_VMAP_STACK=y on x86: stack
accesses that used to be just somewhat questionable are now totally
buggy.
These changes try to do it without breaking the ABI: the fields are
left there, they are just reporting zero, or reporting narrower
information (the maps file change)"
* 'mm-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
mm: Change vm_is_stack_for_task() to vm_is_stack_for_current()
fs/proc: Stop trying to report thread stacks
fs/proc: Stop reporting eip and esp in /proc/PID/stat
mm/numa: Remove duplicated include from mprotect.c
Pull irq fixes from Ingo Molnar:
"Mostly irqchip driver fixes, plus a symbol export"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
kernel/irq: Export irq_set_parent()
irqchip/gic: Add missing \n to CPU IF adjustment message
irqchip/jcore: Don't show Kconfig menu item for driver
irqchip/eznps: Drop pointless static qualifier in nps400_of_init()
irqchip/gic-v3-its: Fix entry size mask for GITS_BASER
irqchip/gic-v3-its: Fix 64bit GIC{R,ITS}_TYPER accesses
Pull EFI fixes from Ingo Molnar:
"Add Ard Biesheuvel as EFI co-maintainer, plus fix an ARM build bug
with older toolchains"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/arm: Fix absolute relocation detection for older toolchains
MAINTAINERS: Add myself as EFI maintainer
Pull powerpc fixes from Michael Ellerman:
"Fixes marked for stable:
- Prevent unlikely crash in copro_calculate_slb() (Frederic Barrat)
- cxl: Prevent adapter reset if an active context exists (Vaibhav Jain)
Fixes for code merged this cycle:
- Fix boot on systems with uncompressed kernel image (Heiner Kallweit)
- Drop dump_numa_memory_topology() (Michael Ellerman)
- Fix numa topology console print (Aneesh Kumar K.V)
- Ignore the pkey system calls for now (Stephen Rothwell)"
* tag 'powerpc-4.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Ignore the pkey system calls for now
powerpc: Fix numa topology console print
powerpc/mm: Drop dump_numa_memory_topology()
cxl: Prevent adapter reset if an active context exists
powerpc/boot: Fix boot on systems with uncompressed kernel image
powerpc/mm: Prevent unlikely crash in copro_calculate_slb()
Pull NFS client bugfixes from Anna Schumaker:
"Just two bugfixes this time:
Stable bugfix:
- Fix last_write_offset incorrectly set to page boundary
Other bugfix:
- Fix missing-braces warning"
* tag 'nfs-for-4.9-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
nfs4: fix missing-braces warning
pnfs/blocklayout: fix last_write_offset incorrectly set to page boundary
Pull ACPI fixes from Rafael Wysocki:
"These fix an issue related to system resume in the new WDAT-based
watchdog driver and a return value of a stub function in the ACPI CPPC
framework.
Specifics:
- Update the ACPI WDAT-based watchdog driver to ping the hardware
during system resume to prevent a reset from occurring after the
resume is complete (Mika Westerberg).
- Fix the return value of the pcc_mbox_request_channel() stub for
CONFIG_PCC unset (Hoan Tran)"
* tag 'acpi-4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
watchdog: wdat_wdt: Ping the watchdog on resume
mailbox: PCC: Fix return value of pcc_mbox_request_channel()
Pull GIC updates from Marc Zyngier:
- Fix for 32bit accesses that should be 64bit on 64bit machines
- Fix for a field decoding macro
- Beautify a warning message