07 May, 2020
1 commit
-
eventfd is using ->read() as it's file_operations read handler, but
this prevents passing in information about whether a given IO operation
is blocking or not. We can only use the file flags for that. To support
async (-EAGAIN/poll based) retries for io_uring, we need ->read_iter()
support. Convert eventfd to using ->read_iter().With ->read_iter(), we can support IOCB_NOWAIT. Ensure the fd setup
is done such that we set file->f_mode with FMODE_NOWAIT.[missing include added]
Signed-off-by: Jens Axboe
Signed-off-by: Al Viro
13 Apr, 2020
10 commits
-
This sorts the actual field names too, potentially causing even more
chaos and confusion at merge time if you have edited the MAINTAINERS
file. But the end result is a more consistent layout, and hopefully
it's a one-time pain minimized by doing this just before the -rc1
release.This was entirely scripted:
./scripts/parse-maintainers.pl --input=MAINTAINERS --output=MAINTAINERS --order
Requested-by: Joe Perches
Signed-off-by: Linus Torvalds -
They are all supposed to be sorted, but people who add new entries don't
always know the alphabet. Plus sometimes the entry names get edited,
and people don't then re-order the entry.Let's see how painful this will be for merging purposes (the MAINTAINERS
file is often edited in various different trees), but Joe claims there's
relatively few patches in -next that touch this, and doing it just
before -rc1 is likely the best time. Fingers crossed.This was scripted with
/scripts/parse-maintainers.pl --input=MAINTAINERS --output=MAINTAINERS
but then I also ended up manually upper-casing a few entry names that
stood out when looking at the end result.Requested-by: Joe Perches
Signed-off-by: Linus Torvalds -
Pull x86 fixes from Thomas Gleixner:
"A set of three patches to fix the fallout of the newly added split
lock detection feature.It addressed the case where a KVM guest triggers a split lock #AC and
KVM reinjects it into the guest which is not prepared to handle it.Add proper sanity checks which prevent the unconditional injection
into the guest and handles the #AC on the host side in the same way as
user space detections are handled. Depending on the detection mode it
either warns and disables detection for the task or kills the task if
the mode is set to fatal"* tag 'x86-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
KVM: VMX: Extend VMXs #AC interceptor to handle split lock #AC in guest
KVM: x86: Emulate split-lock access as a write in emulator
x86/split_lock: Provide handle_guest_split_lock() -
Pull time(keeping) updates from Thomas Gleixner:
- Fix the time_for_children symlink in /proc/$PID/ so it properly
reflects that it part of the 'time' namespace- Add the missing userns limit for the allowed number of time
namespaces, which was half defined but the actual array member was
not added. This went unnoticed as the array has an exessive empty
member at the end but introduced a user visible regression as the
output was corrupted.- Prevent further silent ucount corruption by adding a BUILD_BUG_ON()
to catch half updated data.* tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ucount: Make sure ucounts in /proc/sys/user don't regress again
time/namespace: Add max_time_namespaces ucount
time/namespace: Fix time_for_children symlink -
Pull scheduler fixes/updates from Thomas Gleixner:
- Deduplicate the average computations in the scheduler core and the
fair class code.- Fix a raise between runtime distribution and assignement which can
cause exceeding the quota by up to 70%.- Prevent negative results in the imbalanace calculation
- Remove a stale warning in the workqueue code which can be triggered
since the call site was moved out of preempt disabled code. It's a
false positive.- Deduplicate the print macros for procfs
- Add the ucmap values to the SCHED_DEBUG procfs output for completness
* tag 'sched-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/debug: Add task uclamp values to SCHED_DEBUG procfs
sched/debug: Factor out printing formats into common macros
sched/debug: Remove redundant macro define
sched/core: Remove unused rq::last_load_update_tick
workqueue: Remove the warning in wq_worker_sleeping()
sched/fair: Fix negative imbalance in imbalance calculation
sched/fair: Fix race between runtime distribution and assignment
sched/fair: Align rq->avg_idle and rq->avg_scan_cost -
Pull perf fixes from Thomas Gleixner:
"Three fixes/updates for perf:- Fix the perf event cgroup tracking which tries to track the cgroup
even for disabled events.- Add Ice Lake server support for uncore events
- Disable pagefaults when retrieving the physical address in the
sampling code"* tag 'perf-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Disable page faults when getting phys address
perf/x86/intel/uncore: Add Ice Lake server uncore support
perf/cgroup: Correct indirection in perf_less_group_idx()
perf/core: Fix event cgroup tracking -
Pull locking fixes from Thomas Gleixner:
"Three small fixes/updates for the locking core code:- Plug a task struct reference leak in the percpu rswem
implementation.- Document the refcount interaction with PID_MAX_LIMIT
- Improve the 'invalid wait context' data dump in lockdep so it
contains all information which is required to decode the problem"* tag 'locking-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Improve 'invalid wait context' splat
locking/refcount: Document interaction with PID_MAX_LIMIT
locking/percpu-rwsem: Fix a task_struct refcount -
Pull cifs fixes from Steve French:
"Ten cifs/smb fixes:- five RDMA (smbdirect) related fixes
- add experimental support for swap over SMB3 mounts
- also a fix which improves performance of signed connections"
* tag '5.7-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
smb3: enable swap on SMB3 mounts
smb3: change noisy error message to FYI
smb3: smbdirect support can be configured by default
cifs: smbd: Do not schedule work to send immediate packet on every receive
cifs: smbd: Properly process errors on ib_post_send
cifs: Allocate crypto structures on the fly for calculating signatures of incoming packets
cifs: smbd: Update receive credits before sending and deal with credits roll back on failure before sending
cifs: smbd: Check send queue size before posting a send
cifs: smbd: Merge code to track pending packets
cifs: ignore cached share root handle closing errors -
Pull NFS client bugfix from Trond Myklebust:
"Fix an RCU read lock leakage in pnfs_alloc_ds_commits_list()"* tag 'nfs-for-5.7-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
pNFS: Fix RCU lock leakage
12 Apr, 2020
4 commits
-
Pull nios2 updates from Ley Foon Tan:
- Remove nios2-dev@lists.rocketboards.org from MAINTAINERS
- remove 'resetvalue' property
- rename 'altr,gpio-bank-width' -> 'altr,ngpio'
- enable the common clk subsystem on Nios2
* tag 'nios2-v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan/nios2:
MAINTAINERS: Remove nios2-dev@lists.rocketboards.org
arch: nios2: remove 'resetvalue' property
arch: nios2: rename 'altr,gpio-bank-width' -> 'altr,ngpio'
arch: nios2: Enable the common clk subsystem on Nios2 -
Pull dma-mapping fixes from Christoph Hellwig:
- fix an integer truncation in dma_direct_get_required_mask
(Kishon Vijay Abraham)- fix the display of dma mapping types (Grygorii Strashko)
* tag 'dma-mapping-5.7-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-debug: fix displaying of dma allocation type
dma-direct: fix data truncation in dma_direct_get_required_mask() -
Pull more Kbuild updates from Masahiro Yamada:
- raise minimum supported binutils version to 2.23
- remove old CONFIG_AS_* macros that we know binutils >= 2.23 supports
- move remaining CONFIG_AS_* tests to Kconfig from Makefile
- enable -Wtautological-compare warnings to catch more issues
- do not support GCC plugins for GCC =2.23, supporting ADX and AVX2
crypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean'
... -
I do not longer work for credativ Germany.
Please, use my private email address instead.
This is for the case when people want to CC me on
patches sent from my old business email address.Signed-off-by: Sedat Dilek
Signed-off-by: Linus Torvalds
11 Apr, 2020
25 commits
-
Another brown paper bag moment. pnfs_alloc_ds_commits_list() is leaking
the RCU lock.Fixes: a9901899b649 ("pNFS: Add infrastructure for cleaning up per-layout commit structures")
Signed-off-by: Trond Myklebust -
Two types of #AC can be generated in Intel CPUs:
1. legacy alignment check #AC
2. split lock #ACReflect #AC back into the guest if the guest has legacy alignment checks
enabled or if split lock detection is disabled.If the #AC is not a legacy one and split lock detection is enabled, then
invoke handle_guest_split_lock() which will either warn and disable split
lock detection for this task or force SIGBUS on it.[ tglx: Switch it to handle_guest_split_lock() and rename the misnamed
helper function. ]Suggested-by: Sean Christopherson
Signed-off-by: Xiaoyao Li
Signed-off-by: Sean Christopherson
Signed-off-by: Thomas Gleixner
Signed-off-by: Borislav Petkov
Acked-by: Paolo Bonzini
Link: https://lkml.kernel.org/r/20200410115517.176308876@linutronix.de -
Emulate split-lock accesses as writes if split lock detection is on
to avoid #AC during emulation, which will result in a panic(). This
should never occur for a well-behaved guest, but a malicious guest can
manipulate the TLB to trigger emulation of a locked instruction[1].More discussion can be found at [2][3].
[1] https://lkml.kernel.org/r/8c5b11c9-58df-38e7-a514-dc12d687b198@redhat.com
[2] https://lkml.kernel.org/r/20200131200134.GD18946@linux.intel.com
[3] https://lkml.kernel.org/r/20200227001117.GX9940@linux.intel.comSuggested-by: Sean Christopherson
Signed-off-by: Xiaoyao Li
Signed-off-by: Sean Christopherson
Signed-off-by: Thomas Gleixner
Signed-off-by: Borislav Petkov
Acked-by: Paolo Bonzini
Link: https://lkml.kernel.org/r/20200410115517.084300242@linutronix.de -
Without at least minimal handling for split lock detection induced #AC,
VMX will just run into the same problem as the VMWare hypervisor, which
was reported by Kenneth.It will inject the #AC blindly into the guest whether the guest is
prepared or not.Provide a function for guest mode which acts depending on the host
SLD mode. If mode == sld_warn, treat it like user space, i.e. emit a
warning, disable SLD and mark the task accordingly. Otherwise force
SIGBUS.[ bp: Add a !CPU_SUP_INTEL stub for handle_guest_split_lock(). ]
Signed-off-by: Thomas Gleixner
Signed-off-by: Borislav Petkov
Acked-by: Paolo Bonzini
Link: https://lkml.kernel.org/r/20200410115516.978037132@linutronix.de
Link: https://lkml.kernel.org/r/20200402123258.895628824@linutronix.de -
The keyword here is 'twice' to explain the trick.
Signed-off-by: Masahiro Yamada
-
Merge yet more updates from Andrew Morton:
- Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc,
gup, hugetlb, pagemap, memremap)- Various other things (hfs, ocfs2, kmod, misc, seqfile)
* akpm: (34 commits)
ipc/util.c: sysvipc_find_ipc() should increase position index
kernel/gcov/fs.c: gcov_seq_next() should increase position index
fs/seq_file.c: seq_read(): add info message about buggy .next functions
drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings
change email address for Pali Rohár
selftests: kmod: test disabling module autoloading
selftests: kmod: fix handling test numbers above 9
docs: admin-guide: document the kernel.modprobe sysctl
fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
kmod: make request_module() return an error when autoloading is disabled
mm/memremap: set caching mode for PCI P2PDMA memory to WC
mm/memory_hotplug: add pgprot_t to mhp_params
powerpc/mm: thread pgprot_t through create_section_mapping()
x86/mm: introduce __set_memory_prot()
x86/mm: thread pgprot_t through init_memory_mapping()
mm/memory_hotplug: rename mhp_restrictions to mhp_params
mm/memory_hotplug: drop the flags field from struct mhp_restrictions
mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
mm/vma: introduce VM_ACCESS_FLAGS
mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
... -
Pull Documentation fixes from Jonathan Corbet:
"A handful of late-arriving fixes for the documentation tree"* tag 'docs-5.7-2' of git://git.lwn.net/linux:
Documentation: android: binderfs: add 'stats' mount option
Documentation: driver-api/usb/writing_usb_driver.rst Updates documentation links
docs: driver-api: address duplicate label warning
Documentation: sysrq: fix RST formatting
docs: kernel-parameters.txt: Fix broken references
docs: kernel-parameters.txt: Remove nompx
docs: filesystems: fix typo in qnx6.rst -
Pull orangefs updates from Mike Marshall:
"A fix and two cleanups.Fix:
- Christoph Hellwig noticed that some logic I added to
orangefs_file_read_iter introduced a race condition, so he sent a
reversion patch. I had to modify his patch since reverting at this
point broke Orangefs.Cleanups:
- Christoph Hellwig noticed that we were doing some unnecessary work
in orangefs_flush, so he sent in a patch that removed the un-needed
code.- Al Viro told me he had trouble building Orangefs. Orangefs should
be easy to build, even for Al :-).I looked back at the test server build notes in orangefs.txt, just
in case that's where the trouble really is, and found a couple of
typos and made a couple of clarifications"* tag 'for-linus-5.7-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: clarify build steps for test server in orangefs.txt
orangefs: don't mess with I_DIRTY_TIMES in orangefs_flush
orangefs: get rid of knob code... -
Pull xtensa updates from Max Filippov:
- replace setup_irq() by request_irq()
- cosmetic fixes in xtensa Kconfig and boot/Makefile
* tag 'xtensa-20200410' of git://github.com/jcmvbkbc/linux-xtensa:
arch/xtensa: fix grammar in Kconfig help text
xtensa: remove meaningless export ccflags-y
xtensa: replace setup_irq() by request_irq() -
Pull more xen updates from Juergen Gross:
- two cleanups
- fix a boot regression introduced in this merge window
- fix wrong use of memory allocation flags
* tag 'for-linus-5.7-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: fix booting 32-bit pv guest
x86/xen: make xen_pvmmu_arch_setup() static
xen/blkfront: fix memory allocation flags in blkfront_setup_indirect()
xen: Use evtchn_type_t as a type for event channels -
If seq_file .next function does not change position index, read after
some lseek can generate unexpected output.https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin
Signed-off-by: Andrew Morton
Acked-by: Waiman Long
Cc: Davidlohr Bueso
Cc: Manfred Spraul
Cc: Al Viro
Cc: Ingo Molnar
Cc: NeilBrown
Cc: Peter Oberparleiter
Cc: Steven Rostedt
Link: http://lkml.kernel.org/r/b7a20945-e315-8bb0-21e6-3875c14a8494@virtuozzo.com
Signed-off-by: Linus Torvalds -
If seq_file .next function does not change position index, read after
some lseek can generate unexpected output.https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin
Signed-off-by: Andrew Morton
Acked-by: Peter Oberparleiter
Cc: Al Viro
Cc: Davidlohr Bueso
Cc: Ingo Molnar
Cc: Manfred Spraul
Cc: NeilBrown
Cc: Steven Rostedt
Cc: Waiman Long
Link: http://lkml.kernel.org/r/f65c6ee7-bd00-f910-2f8a-37cc67e4ff88@virtuozzo.com
Signed-off-by: Linus Torvalds -
Patch series "seq_file .next functions should increase position index".
In Aug 2018 NeilBrown noticed commit 1f4aace60b0e ("fs/seq_file.c:
simplify seq_file iteration code and interface")"Some ->next functions do not increment *pos when they return NULL...
Note that such ->next functions are buggy and should be fixed. A simple
demonstration is dd if=/proc/swaps bs=1000 skip=1 Choose any block size
larger than the size of /proc/swaps. This will always show the whole
last line of /proc/swaps"Described problem is still actual. If you make lseek into middle of
last output line following read will output end of last line and whole
last line once again.$ dd if=/proc/swaps bs=1 # usual output
Filename Type Size Used Priority
/dev/dm-0 partition 4194812 97536 -2
104+0 records in
104+0 records out
104 bytes copied$ dd if=/proc/swaps bs=40 skip=1 # last line was generated twice
dd: /proc/swaps: cannot skip to specified offset
v/dm-0 partition 4194812 97536 -2
/dev/dm-0 partition 4194812 97536 -2
3+1 records in
3+1 records out
131 bytes copiedThere are lot of other affected files, I've found 30+ including
/proc/net/ip_tables_matches and /proc/sysvipc/*I've sent patches into maillists of affected subsystems already, this
patch-set fixes the problem in files related to pstore, tracing, gcov,
sysvipc and other subsystems processed via linux-kernel@ mailing list
directlyhttps://bugzilla.kernel.org/show_bug.cgi?id=206283
This patch (of 4):
Add debug code to seq_read() to detect missed or out-of-tree incorrect
.next seq_file functions.[akpm@linux-foundation.org: s/pr_info/pr_info_ratelimited/, per Qian Cai]
https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin
Signed-off-by: Andrew Morton
Cc: NeilBrown
Cc: Al Viro
Cc: Steven Rostedt
Cc: Davidlohr Bueso
Cc: Ingo Molnar
Cc: Manfred Spraul
Cc: Peter Oberparleiter
Cc: Waiman Long
Link: http://lkml.kernel.org/r/244674e5-760c-86bd-d08a-047042881748@virtuozzo.com
Link: http://lkml.kernel.org/r/7c24087c-e280-e580-5b0c-0cdaeb14cd18@virtuozzo.com
Signed-off-by: Linus Torvalds -
Remove dev_err() messages after platform_get_irq*() failures.
platform_get_irq() already prints an error.Generated by: scripts/coccinelle/api/platform_get_irq.cocci
Fixes: 6c41ac96ad92 ("dmaengine: tegra-apb: Support COMPILE_TEST")
Signed-off-by: kbuild test robot
Signed-off-by: Julia Lawall
Signed-off-by: Andrew Morton
Reviewed-by: Dmitry Osipenko
Acked-by: Thierry Reding
Cc: Laxman Dewangan
Cc: Vinod Koul
Cc: Stephen Warren
Cc: Jon Hunter
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2002271133450.2973@hadrien
Signed-off-by: Linus Torvalds -
For security reasons I stopped using gmail account and kernel address is
now up-to-date alias to my personal address.People periodically send me emails to address which they found in source
code of drivers, so this change reflects state where people can contact
me.[ Added .mailmap entry as per Joe Perches - Linus ]
Signed-off-by: Pali Rohár
Signed-off-by: Andrew Morton
Cc: Greg Kroah-Hartman
Cc: Joe Perches
Link: http://lkml.kernel.org/r/20200307104237.8199-1-pali@kernel.org
Signed-off-by: Linus Torvalds -
Test that request_module() fails with -ENOENT when
/proc/sys/kernel/modprobe contains (a) a nonexistent path, and (b) an
empty path.Case (b) is a regression test for the patch "kmod: make request_module()
return an error when autoloading is disabled".Tested with 'kmod.sh -t 0010 && kmod.sh -t 0011', and also simply with
'kmod.sh' to run all kmod tests.Signed-off-by: Eric Biggers
Signed-off-by: Andrew Morton
Acked-by: Luis Chamberlain
Cc: Alexei Starovoitov
Cc: Greg Kroah-Hartman
Cc: Jeff Vander Stoep
Cc: Jessica Yu
Cc: Kees Cook
Cc: NeilBrown
Link: http://lkml.kernel.org/r/20200312202552.241885-5-ebiggers@kernel.org
Signed-off-by: Linus Torvalds -
get_test_count() and get_test_enabled() were broken for test numbers
above 9 due to awk interpreting a field specification like '$0010' as
octal rather than decimal. Fix it by stripping the leading zeroes.Signed-off-by: Eric Biggers
Signed-off-by: Andrew Morton
Acked-by: Luis Chamberlain
Cc: Alexei Starovoitov
Cc: Greg Kroah-Hartman
Cc: Jeff Vander Stoep
Cc: Jessica Yu
Cc: Kees Cook
Cc: NeilBrown
Link: http://lkml.kernel.org/r/20200318230515.171692-5-ebiggers@kernel.org
Signed-off-by: Linus Torvalds -
Document the kernel.modprobe sysctl in the same place that all the other
kernel.* sysctls are documented. Make sure to mention how to use this
sysctl to completely disable module autoloading, and how this sysctl
relates to CONFIG_STATIC_USERMODEHELPER.[ebiggers@google.com: v5]
Link: http://lkml.kernel.org/r/20200318230515.171692-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers
Signed-off-by: Andrew Morton
Cc: Alexei Starovoitov
Cc: Greg Kroah-Hartman
Cc: Jeff Vander Stoep
Cc: Jessica Yu
Cc: Kees Cook
Cc: Luis Chamberlain
Cc: NeilBrown
Link: http://lkml.kernel.org/r/20200312202552.241885-4-ebiggers@kernel.org
Signed-off-by: Linus Torvalds -
After request_module(), nothing is stopping the module from being
unloaded until someone takes a reference to it via try_get_module().The WARN_ONCE() in get_fs_type() is thus user-reachable, via userspace
running 'rmmod' concurrently.Since WARN_ONCE() is for kernel bugs only, not for user-reachable
situations, downgrade this warning to pr_warn_once().Keep it printed once only, since the intent of this warning is to detect
a bug in modprobe at boot time. Printing the warning more than once
wouldn't really provide any useful extra information.Fixes: 41124db869b7 ("fs: warn in case userspace lied about modprobe return")
Signed-off-by: Eric Biggers
Signed-off-by: Andrew Morton
Reviewed-by: Jessica Yu
Cc: Alexei Starovoitov
Cc: Greg Kroah-Hartman
Cc: Jeff Vander Stoep
Cc: Jessica Yu
Cc: Kees Cook
Cc: Luis Chamberlain
Cc: NeilBrown
Cc: [4.13+]
Link: http://lkml.kernel.org/r/20200312202552.241885-3-ebiggers@kernel.org
Signed-off-by: Linus Torvalds -
Patch series "module autoloading fixes and cleanups", v5.
This series fixes a bug where request_module() was reporting success to
kernel code when module autoloading had been completely disabled via
'echo > /proc/sys/kernel/modprobe'.It also addresses the issues raised on the original thread
(https://lkml.kernel.org/lkml/20200310223731.126894-1-ebiggers@kernel.org/T/#u)
bydocumenting the modprobe sysctl, adding a self-test for the empty path
case, and downgrading a user-reachable WARN_ONCE().This patch (of 4):
It's long been possible to disable kernel module autoloading completely
(while still allowing manual module insertion) by setting
/proc/sys/kernel/modprobe to the empty string.This can be preferable to setting it to a nonexistent file since it
avoids the overhead of an attempted execve(), avoids potential
deadlocks, and avoids the call to security_kernel_module_request() and
thus on SELinux-based systems eliminates the need to write SELinux rules
to dontaudit module_request.However, when module autoloading is disabled in this way,
request_module() returns 0. This is broken because callers expect 0 to
mean that the module was successfully loaded.Apparently this was never noticed because this method of disabling
module autoloading isn't used much, and also most callers don't use the
return value of request_module() since it's always necessary to check
whether the module registered its functionality or not anyway.But improperly returning 0 can indeed confuse a few callers, for example
get_fs_type() in fs/filesystems.c where it causes a WARNING to be hit:if (!fs && (request_module("fs-%.*s", len, name) == 0)) {
fs = __get_fs_type(name, len);
WARN_ONCE(!fs, "request_module fs-%.*s succeeded, but still no fs?\n", len, name);
}This is easily reproduced with:
echo > /proc/sys/kernel/modprobe
mount -t NONEXISTENT none /It causes:
request_module fs-NONEXISTENT succeeded, but still no fs?
WARNING: CPU: 1 PID: 1106 at fs/filesystems.c:275 get_fs_type+0xd6/0xf0
[...]This should actually use pr_warn_once() rather than WARN_ONCE(), since
it's also user-reachable if userspace immediately unloads the module.
Regardless, request_module() should correctly return an error when it
fails. So let's make it return -ENOENT, which matches the error when
the modprobe binary doesn't exist.I've also sent patches to document and test this case.
Signed-off-by: Eric Biggers
Signed-off-by: Andrew Morton
Reviewed-by: Kees Cook
Reviewed-by: Jessica Yu
Acked-by: Luis Chamberlain
Cc: Alexei Starovoitov
Cc: Greg Kroah-Hartman
Cc: Jeff Vander Stoep
Cc: Ben Hutchings
Cc: Josh Triplett
Cc:
Link: http://lkml.kernel.org/r/20200310223731.126894-1-ebiggers@kernel.org
Link: http://lkml.kernel.org/r/20200312202552.241885-1-ebiggers@kernel.org
Signed-off-by: Linus Torvalds -
PCI BAR IO memory should never be mapped as WB, however prior to this
the PAT bits were set WB and it was typically overridden by MTRR
registers set by the firmware.Set PCI P2PDMA memory to be UC as this is what it currently, typically,
ends up being mapped as on x86 after the MTRR registers override the
cache setting.Future use-cases may need to generalize this by adding flags to select
the caching type, as some P2PDMA cases may not want UC. However, those
use-cases are not upstream yet and this can be changed when they arrive.Signed-off-by: Logan Gunthorpe
Signed-off-by: Andrew Morton
Reviewed-by: Dan Williams
Cc: Christoph Hellwig
Cc: Jason Gunthorpe
Cc: Andy Lutomirski
Cc: Benjamin Herrenschmidt
Cc: Borislav Petkov
Cc: Catalin Marinas
Cc: Dave Hansen
Cc: David Hildenbrand
Cc: Eric Badger
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Hocko
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Will Deacon
Link: http://lkml.kernel.org/r/20200306170846.9333-8-logang@deltatee.com
Signed-off-by: Linus Torvalds -
devm_memremap_pages() is currently used by the PCI P2PDMA code to create
struct page mappings for IO memory. At present, these mappings are
created with PAGE_KERNEL which implies setting the PAT bits to be WB.
However, on x86, an mtrr register will typically override this and force
the cache type to be UC-. In the case firmware doesn't set this
register it is effectively WB and will typically result in a machine
check exception when it's accessed.Other arches are not currently likely to function correctly seeing they
don't have any MTRR registers to fall back on.To solve this, provide a way to specify the pgprot value explicitly to
arch_add_memory().Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a
simple change to pass the pgprot_t down to their respective functions
which set up the page tables. For x86_32, set the page tables
explicitly using _set_memory_prot() (seeing they are already mapped).For ia64, s390 and sh, reject anything but PAGE_KERNEL settings -- this
should be fine, for now, seeing these architectures don't support
ZONE_DEVICE.A check in __add_pages() is also added to ensure the pgprot parameter
was set for all arches.Signed-off-by: Logan Gunthorpe
Signed-off-by: Andrew Morton
Acked-by: David Hildenbrand
Acked-by: Michal Hocko
Acked-by: Dan Williams
Cc: Andy Lutomirski
Cc: Benjamin Herrenschmidt
Cc: Borislav Petkov
Cc: Catalin Marinas
Cc: Christoph Hellwig
Cc: Dave Hansen
Cc: Eric Badger
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: Jason Gunthorpe
Cc: Michael Ellerman
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Will Deacon
Link: http://lkml.kernel.org/r/20200306170846.9333-7-logang@deltatee.com
Signed-off-by: Linus Torvalds -
In prepartion to support a pgprot_t argument for arch_add_memory().
Signed-off-by: Logan Gunthorpe
Signed-off-by: Andrew Morton
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: Andy Lutomirski
Cc: Borislav Petkov
Cc: Catalin Marinas
Cc: Christoph Hellwig
Cc: Dan Williams
Cc: Dave Hansen
Cc: David Hildenbrand
Cc: Eric Badger
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: Jason Gunthorpe
Cc: Michal Hocko
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Will Deacon
Link: http://lkml.kernel.org/r/20200306170846.9333-6-logang@deltatee.com
Signed-off-by: Linus Torvalds -
For use in the 32bit arch_add_memory() to set the pgprot type of the
memory to add.Signed-off-by: Logan Gunthorpe
Signed-off-by: Andrew Morton
Reviewed-by: Dan Williams
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: Borislav Petkov
Cc: "H. Peter Anvin"
Cc: Dave Hansen
Cc: Andy Lutomirski
Cc: Peter Zijlstra
Cc: Benjamin Herrenschmidt
Cc: Catalin Marinas
Cc: Christoph Hellwig
Cc: David Hildenbrand
Cc: Eric Badger
Cc: Jason Gunthorpe
Cc: Michael Ellerman
Cc: Michal Hocko
Cc: Paul Mackerras
Cc: Will Deacon
Link: http://lkml.kernel.org/r/20200306170846.9333-5-logang@deltatee.com
Signed-off-by: Linus Torvalds -
In preparation to support a pgprot_t argument for arch_add_memory().
It's required to move the prototype of init_memory_mapping() seeing the
original location came before the definition of pgprot_t.Signed-off-by: Logan Gunthorpe
Signed-off-by: Andrew Morton
Reviewed-by: Dan Williams
Acked-by: Michal Hocko
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: Borislav Petkov
Cc: "H. Peter Anvin"
Cc: Dave Hansen
Cc: Andy Lutomirski
Cc: Peter Zijlstra
Cc: Benjamin Herrenschmidt
Cc: Catalin Marinas
Cc: Christoph Hellwig
Cc: David Hildenbrand
Cc: Eric Badger
Cc: Jason Gunthorpe
Cc: Michael Ellerman
Cc: Paul Mackerras
Cc: Will Deacon
Link: http://lkml.kernel.org/r/20200306170846.9333-4-logang@deltatee.com
Signed-off-by: Linus Torvalds
