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Linux kernel
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Pull dax fixes from Dan Williams:
"A filesystem-dax and device-dax fix for v5.3.
The filesystem-dax fix is tagged for stable as the implementation has
been mistakenly throwing away all cow pages on any truncate or hole
punch operation as part of the solution to coordinate device-dma vs
truncate to dax pages.
The device-dax change fixes up a regression this cycle from the
introduction of a common 'internal per-cpu-ref' implementation.
Summary:
- Fix dax_layout_busy_page() to not discard private cow pages of
fs/dax private mappings.
- Update the memremap_pages core to properly cleanup on behalf of
internal reference-count users like device-dax"
* tag 'dax-fixes-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
mm/memremap: Fix reuse of pgmap instances with internal references
dax: dax_layout_busy_page() should not unmap cow pages
Pull NTB fix from Jon Mason:
"Bug fix for NTB MSI kernel compile warning"
* tag 'ntb-5.3-bugfixes' of git://github.com/jonmason/ntb:
NTB/msi: remove incorrect MODULE defines
Currently, attempts to shutdown and re-enable a device-dax instance
trigger:
Missing reference count teardown definition
WARNING: CPU: 37 PID: 1608 at mm/memremap.c:211 devm_memremap_pages+0x234/0x850
[..]
RIP: 0010:devm_memremap_pages+0x234/0x850
[..]
Call Trace:
dev_dax_probe+0x66/0x190 [device_dax]
really_probe+0xef/0x390
driver_probe_device+0xb4/0x100
device_driver_attach+0x4f/0x60
Given that the setup path initializes pgmap->ref, arrange for it to be
also torn down so devm_memremap_pages() is ready to be called again and
not be mistaken for the 3rd-party per-cpu-ref case.
Fixes: 24917f6b1041 ("memremap: provide an optional internal refcount in struct dev_pagemap")
Reported-by: Fan Du <fan.du@intel.com>
Tested-by: Vishal Verma <vishal.l.verma@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/156530042781.2068700.8733813683117819799.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull RISC-V updates from Paul Walmsley:
"A few minor RISC-V updates for v5.3-rc4:
- Remove __udivdi3() from the 32-bit Linux port, converting the only
upstream user to use do_div(), per Linux policy
- Convert the RISC-V standard clocksource away from per-cpu data
structures, since only one is used by Linux, even on a multi-CPU
system
- A set of DT binding updates that remove an obsolete text binding in
favor of a YAML binding, fix a bogus compatible string in the
schema (thus fixing a "make dtbs_check" warning), and clarifies the
future values expected in one of the RISC-V CPU properties"
* tag 'riscv/for-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
dt-bindings: riscv: fix the schema compatible string for the HiFive Unleashed board
dt-bindings: riscv: remove obsolete cpus.txt
RISC-V: Remove udivdi3
riscv: delay: use do_div() instead of __udivdi3()
dt-bindings: Update the riscv,isa string description
RISC-V: Remove per cpu clocksource
msi.c is not a module on its own right and should not have the
MODULE_[LICENSE|VERSION|AUTHOR|DESCRIPTION] definitions.
This caused a regression noticed by lkp with the following back
trace:
WARNING: CPU: 0 PID: 1 at kernel/params.c:861 param_sysfs_init+0xb1/0x20a
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc1-00018-g26b3a37b928457 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
RIP: 0010:param_sysfs_init+0xb1/0x20a
Code: 24 38 e8 ec 17 2e fd 49 8b 7c 24 38 e8 76 fe ff ff 48 85 c0 48 89 c5 74 25 31 d2 4c 89 e6 48 89 c7 e8 6d 6f 3c fd 85 c0 74 02 <0f> 0b 48 89 ef 31 f6 e8 5d 70 a7 fe 48 89 ef e8 95 52 a7 fe 48 83
RSP: 0000:ffff88806b0ffe30 EFLAGS: 00010282
RAX: 00000000ffffffef RBX: ffffffff83774220 RCX: ffff88806a85e880
RDX: 00000000ffffffef RSI: ffff88806b000400 RDI: ffff88806a8608c0
RBP: ffff88806b392000 R08: ffffed100d61ff59 R09: ffffed100d61ff59
R10: 0000000000000001 R11: ffffed100d61ff58 R12: ffffffff83974bc0
R13: 0000000000000004 R14: 0000000000000028 R15: 00000000000003b9
FS: 0000000000000000(0000) GS:ffff88806b800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000000380e000 CR4: 00000000000406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
? file_caps_disable+0x10/0x10
? locate_module_kobject+0xf2/0xf2
do_one_initcall+0x47/0x1f0
kernel_init_freeable+0x1b1/0x243
? rest_init+0xd0/0xd0
kernel_init+0xa/0x130
? calculate_sigpending+0x63/0x80
? rest_init+0xd0/0xd0
ret_from_fork+0x1f/0x30
---[ end trace 78201497ae74cc91 ]---
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 26b3a37b9284 ("NTB: Introduce MSI library")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Vivek:
"As of now dax_layout_busy_page() calls unmap_mapping_range() with last
argument as 1, which says even unmap cow pages. I am wondering who needs
to get rid of cow pages as well.
I noticed one interesting side affect of this. I mount xfs with -o dax and
mmaped a file with MAP_PRIVATE and wrote some data to a page which created
cow page. Then I called fallocate() on that file to zero a page of file.
fallocate() called dax_layout_busy_page() which unmapped cow pages as well
and then I tried to read back the data I wrote and what I get is old
data from persistent memory. I lost the data I had written. This
read basically resulted in new fault and read back the data from
persistent memory.
This sounds wrong. Are there any users which need to unmap cow pages
as well? If not, I am proposing changing it to not unmap cow pages.
I noticed this while while writing virtio_fs code where when I tried
to reclaim a memory range and that corrupted the executable and I
was running from virtio-fs and program got segment violation."
Dan:
"In fact the unmap_mapping_range() in this path is only to synchronize
against get_user_pages_fast() and force it to call back into the
filesystem to re-establish the mapping. COW pages should be left
untouched by dax_layout_busy_page()."
Cc: <stable@vger.kernel.org>
Fixes: 5fac7408d828 ("mm, fs, dax: handle layout changes to pinned dax mappings")
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: https://lore.kernel.org/r/20190802192956.GA3032@redhat.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull x86 fixes from Thomas Gleixner:
"A few fixes for x86:
- Don't reset the carefully adjusted build flags for the purgatory
and remove the unwanted flags instead. The 'reset all' approach led
to build fails under certain circumstances.
- Unbreak CLANG build of the purgatory by avoiding the builtin
memcpy/memset implementations.
- Address missing prototype warnings by including the proper header
- Fix yet more fall-through issues"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/lib/cpu: Address missing prototypes warning
x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS
x86/purgatory: Do not use __builtin_memcpy and __builtin_memset
x86: mtrr: cyrix: Mark expected switch fall-through
x86/ptrace: Mark expected switch fall-through
The YAML binding document for SiFive boards has an incorrect
compatible string for the HiFive Unleashed board. Change it to match
the name of the board on the SiFive web site:
https://www.sifive.com/boards/hifive-unleashed
which also matches the contents of the board DT data file:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts#n13
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Acked-by: Rob Herring <robh@kernel.org>
Pull perf tooling fixes from Thomas Gleixner:
"Perf tooling fixes all over the place:
- Fix the selection of the main thread COMM in db-export
- Fix the disassemmbly display for BPF in annotate
- Fix cpumap mask setup in perf ftrace when only one CPU is present
- Add the missing 'cpu_clk_unhalted.core' event
- Fix CPU 0 bindings in NUMA benchmarks
- Fix the module size calculations for s390
- Handle the gap between kernel end and module start on s390
correctly
- Build and typo fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf pmu-events: Fix missing "cpu_clk_unhalted.core" event
perf annotate: Fix s390 gap between kernel end and module start
perf record: Fix module size on s390
perf tools: Fix include paths in ui directory
perf tools: Fix a typo in a variable name in the Documentation Makefile
perf cpumap: Fix writing to illegal memory in handling cpumap mask
perf ftrace: Fix failure to set cpumask when only one cpu is present
perf db-export: Fix thread__exec_comm()
perf annotate: Fix printing of unaugmented disassembled instructions from BPF
perf bench numa: Fix cpu0 binding
When building with W=1, warnings about missing prototypes are emitted:
CC arch/x86/lib/cpu.o
arch/x86/lib/cpu.c:5:14: warning: no previous prototype for 'x86_family' [-Wmissing-prototypes]
5 | unsigned int x86_family(unsigned int sig)
| ^~~~~~~~~~
arch/x86/lib/cpu.c:18:14: warning: no previous prototype for 'x86_model' [-Wmissing-prototypes]
18 | unsigned int x86_model(unsigned int sig)
| ^~~~~~~~~
arch/x86/lib/cpu.c:33:14: warning: no previous prototype for 'x86_stepping' [-Wmissing-prototypes]
33 | unsigned int x86_stepping(unsigned int sig)
| ^~~~~~~~~~~~
Add the proper include file so the prototypes are there.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/42513.1565234837@turing-police
Remove the now-obsolete riscv/cpus.txt DT binding document, since we
are using YAML binding documentation instead.
While doing so, transfer the explanatory text about 'harts' (with some
edits) into the YAML file, at Rob's request.
Link: https://lore.kernel.org/linux-riscv/CAL_JsqJs6MtvmuyAknsUxQymbmoV=G+=JfS1PQj9kNHV7fjC9g@mail.gmail.com/
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Rob Herring <robh@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Pull tpm fixes from Jarkko Sakkinen:
"Two bug fixes that did not make into my first pull request"
* tag 'tpmdd-next-20190805' of git://git.infradead.org/users/jjs/linux-tpmdd:
tpm: tpm_ibm_vtpm: Fix unallocated banks
tpm: Fix null pointer dereference on chip register error path
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