This reverts commits 4bad58ebc8bc4f20d89cff95417c9b4674769709 (and
399f8dd9a866e107639eabd3c1979cd526ca3a98, which tried to fix it).

I do not believe these are correct, and I'm about to release 5.13, so am
reverting them out of an abundance of caution.

The locking is odd, and appears broken.

On the allocation side (in __sigqueue_alloc()), the locking is somewhat
straightforward: it depends on sighand->siglock. Since one caller
doesn't hold that lock, it further then tests 'sigqueue_flags' to avoid
the case with no locks held.

On the freeing side (in sigqueue_cache_or_free()), there is no locking
at all, and the logic instead depends on 'current' being a single
thread, and not able to race with itself.

To make things more exciting, there's also the data race between freeing
a signal and allocating one, which is handled by using WRITE_ONCE() and
READ_ONCE(), and being mutually exclusive wrt the initial state (ie
freeing will only free if the old state was NULL, while allocating will
obviously only use the value if it was non-NULL, so only one or the
other will actually act on the value).

However, while the free->alloc paths do seem mutually exclusive thanks
to just the data value dependency, it's not clear what the memory
ordering constraints are on it. Could writes from the previous
allocation possibly be delayed and seen by the new allocation later,
causing logical inconsistencies?

So it's all very exciting and unusual.

And in particular, it seems that the freeing side is incorrect in
depending on "current" being single-threaded. Yes, 'current' is a
single thread, but in the presense of asynchronous events even a single
thread can have data races.

And such asynchronous events can and do happen, with interrupts causing
signals to be flushed and thus free'd (for example - sending a
SIGCONT/SIGSTOP can happen from interrupt context, and can flush
previously queued process control signals).

So regardless of all the other questions about the memory ordering and
locking for this new cached allocation, the sigqueue_cache_or_free()
assumptions seem to be fundamentally incorrect.

It may be that people will show me the errors of my ways, and tell me
why this is all safe after all. We can reinstate it if so. But my
current belief is that the WRITE_ONCE() that sets the cached entry needs
to be a smp_store_release(), and the READ_ONCE() that finds a cached
entry needs to be a smp_load_acquire() to handle memory ordering
correctly.

And the sequence in sigqueue_cache_or_free() would need to either use a
lock or at least be interrupt-safe some way (perhaps by using something
like the percpu 'cmpxchg': it doesn't need to be SMP-safe, but like the
percpu operations it needs to be interrupt-safe).

Fixes: 399f8dd9a866 ("signal: Prevent sigqueue caching after task got released")
Fixes: 4bad58ebc8bc ("signal: Allow tasks to cache one sigqueue struct")
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull s390 fixes from Vasily Gorbik:

- Fix a couple of late pt_regs flags handling findings of conversion to
generic entry.

- Fix potential register clobbering in stack switch helper.

- Fix thread/group masks for offline cpus.

- Fix cleanup of mdev resources when remove callback is invoked in
vfio-ap code.

* tag 's390-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/stack: fix possible register corruption with stack switch helper
s390/topology: clear thread/group maps for offline cpus
s390/vfio-ap: clean up mdev resources when remove callback invoked
s390: clear pt_regs::flags on irq entry
s390: fix system call restart with multiple signals

Pull pin control fixes from Linus Walleij:
"Two last-minute fixes:

- Put an fwnode in the errorpath in the SGPIO driver

- Fix the number of GPIO lines per bank in the STM32 driver"

* tag 'pinctrl-v5.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: stm32: fix the reported number of GPIO lines per bank
pinctrl: microchip-sgpio: Put fwnode in error case during ->probe()

The CALL_ON_STACK macro is used to call a C function from inline
assembly, and therefore must consider the C ABI, which says that only
registers 6-13, and 15 are non-volatile (restored by the called
function).

The inline assembly incorrectly marks all registers used to pass
parameters to the called function as read-only input operands, instead
of operands that are read and written to. This might result in
register corruption depending on usage, compiler, and compile options.

Fix this by marking all operands used to pass parameters as read/write
operands. To keep the code simple even register 6, if used, is marked
as read-write operand.

Fixes: ff340d2472ec ("s390: add stack switch helper")
Cc: <stable@kernel.org> # 4.20
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Pull SCSI fixes from James Bottomley:
"Two small fixes, both in upper layer drivers (scsi disk and cdrom).

The sd one is fixing a commit changing revalidation that came from the
block tree a while ago (5.10) and the sr one adds handling of a
condition we didn't previously handle for manually removed media"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: sd: Call sd_revalidate_disk() for ioctl(BLKRRPART)
scsi: sr: Return appropriate error code when disk is ejected

Each GPIO bank supports a variable number of lines which is usually 16, but
is less in some cases : this is specified by the last argument of the
"gpio-ranges" bank node property.
Report to the framework, the actual number of lines, so the libgpiod
gpioinfo command lists the actually existing GPIO lines.

Fixes: 1dc9d289154b ("pinctrl: stm32: add possibility to use gpio-ranges to declare bank range")
Signed-off-by: Fabien Dessenne <fabien.dessenne@foss.st.com>
Link: https://lore.kernel.org/r/20210617144629.2557693-1-fabien.dessenne@foss.st.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The current code doesn't clear the thread/group maps for offline
CPUs. This may cause kernel crashes like the one bewlow in common
code that assumes if a CPU has sibblings it is online.

Unable to handle kernel pointer dereference in virtual kernel address space

Call Trace:
[<000000013a4b8c3c>] blk_mq_map_swqueue+0x10c/0x388
([<000000013a4b8bcc>] blk_mq_map_swqueue+0x9c/0x388)
[<000000013a4b9300>] blk_mq_init_allocated_queue+0x448/0x478
[<000000013a4b9416>] blk_mq_init_queue+0x4e/0x90
[<000003ff8019d3e6>] loop_add+0x106/0x278 [loop]
[<000003ff801b8148>] loop_init+0x148/0x1000 [loop]
[<0000000139de4924>] do_one_initcall+0x3c/0x1e0
[<0000000139ef449a>] do_init_module+0x6a/0x2a0
[<0000000139ef61bc>] __do_sys_finit_module+0xa4/0xc0
[<0000000139de9e6e>] do_syscall+0x7e/0xd0
[<000000013a8e0aec>] __do_syscall+0xbc/0x110
[<000000013a8ee2e8>] system_call+0x78/0xa0

Fixes: 52aeda7accb6 ("s390/topology: remove offline CPUs from CPU topology masks")
Cc: <stable@kernel.org> # 5.7+
Reported-by: Marius Hillenbrand <mhillen@linux.ibm.com>
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>

Merge misc fixes from Andrew Morton:
"24 patches, based on 4a09d388f2ab382f217a764e6a152b3f614246f6.

Subsystems affected by this patch series: mm (thp, vmalloc, hugetlb,
memory-failure, and pagealloc), nilfs2, kthread, MAINTAINERS, and
mailmap"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (24 commits)
mailmap: add Marek's other e-mail address and identity without diacritics
MAINTAINERS: fix Marek's identity again
mm/page_alloc: do bulk array bounds check after checking populated elements
mm/page_alloc: __alloc_pages_bulk(): do bounds check before accessing array
mm/hwpoison: do not lock page again when me_huge_page() successfully recovers
mm,hwpoison: return -EHWPOISON to denote that the page has already been poisoned
mm/memory-failure: use a mutex to avoid memory_failure() races
mm, futex: fix shared futex pgoff on shmem huge page
kthread: prevent deadlock when kthread_mod_delayed_work() races with kthread_cancel_delayed_work_sync()
kthread_worker: split code for canceling the delayed work timer
mm/vmalloc: unbreak kasan vmalloc support
KVM: s390: prepare for hugepage vmalloc
mm/vmalloc: add vmalloc_no_huge
nilfs2: fix memory leak in nilfs_sysfs_delete_device_group
mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk()
mm/thp: fix page_vma_mapped_walk() if THP mapped by ptes
mm: page_vma_mapped_walk(): get vma_address_end() earlier
mm: page_vma_mapped_walk(): use goto instead of while (1)
mm: page_vma_mapped_walk(): add a level of indentation
mm: page_vma_mapped_walk(): crossing page table boundary
...

While the disk state has nothing to do with partitions, BLKRRPART is used
to force a full revalidate after things like a disk format for historical
reasons. Restore that behavior.

Link: https://lore.kernel.org/r/20210617115504.1732350-1-hch@lst.de
Fixes: 471bd0af544b ("sd: use bdev_check_media_change")
Reported-by: Xiang Chen <chenxiang66@hisilicon.com>
Tested-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

device_for_each_child_node() bumps a reference counting of a returned variable.
We have to balance it whenever we return to the caller.

Fixes: 7e5ea974e61c ("pinctrl: pinctrl-microchip-sgpio: Add pinctrl driver for Microsemi Serial GPIO")
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210606191940.29312-1-andy.shevchenko@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The mdev remove callback for the vfio_ap device driver bails out with
-EBUSY if the mdev is in use by a KVM guest (i.e., the KVM pointer in the
struct ap_matrix_mdev is not NULL). The intended purpose was
to prevent the mdev from being removed while in use. There are two
problems with this scenario:

1. Returning a non-zero return code from the remove callback does not
prevent the removal of the mdev.

2. The KVM pointer in the struct ap_matrix_mdev will always be NULL because
the remove callback will not get invoked until the mdev fd is closed.
When the mdev fd is closed, the mdev release callback is invoked and
clears the KVM pointer from the struct ap_matrix_mdev.

Let's go ahead and remove the check for KVM in the remove callback and
allow the cleanup of mdev resources to proceed.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20210609224634.575156-2-akrowiak@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

This ioctl request reads from uffdio_continue structure written by
userspace which justifies _IOC_WRITE flag. It also writes back to that
structure which justifies _IOC_READ flag.

See NOTEs in include/uapi/asm-generic/ioctl.h for more information.

Fixes: f619147104c8 ("userfaultfd: add UFFDIO_CONTINUE ioctl")
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some of my commits were sent with identities
Marek Behun <marek.behun@nic.cz>
Marek Behún <marek.behun@nic.cz>
while the correct one is
Marek Behún <kabel@kernel.org>

Put this into mailmap so that git shortlog prints all my commits under
one identity.

Link: https://lkml.kernel.org/r/20210616113624.19351-2-kabel@kernel.org
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Handle a reported media event code of 3. This indicates that the media has
been removed from the drive and user intervention is required to proceed.
Return DISK_EVENT_EJECT_REQUEST in that case.

Link: https://lore.kernel.org/r/20210611094402.23884-1-limanyi@uniontech.com
Signed-off-by: ManYi Li <limanyi@uniontech.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

The current irq entry code doesn't initialize pt_regs::flags. On exit to
user mode arch_do_signal_or_restart() tests whether PIF_SYSCALL is set,
which might yield wrong results.

Fix this by clearing pt_regs::flags in the entry.S irq handler
code.

Reported-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Fixes: 56e62a737028 ("s390: convert to generic entry")
Cc: <stable@vger.kernel.org> # 5.12
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Pull i2c fixes from Wolfram Sang:
"Three more driver bugfixes and an annotation fix for the core"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: robotfuzz-osif: fix control-request directions
i2c: dev: Add __user annotation
i2c: cp2615: check for allocation failure in cp2615_i2c_recv()
i2c: i801: Ensure that SMBHSTSTS_INUSE_STS is cleared when leaving i801_access

Fix my name to use diacritics, since MAINTAINERS supports it.

Fix my e-mail address in MAINTAINERS' marvell10g PHY driver description,
I accidentally put my other e-mail address here.

Link: https://lkml.kernel.org/r/20210616113624.19351-1-kabel@kernel.org
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

get_device(shost->shost_gendev.parent) is called after host state has
switched to SHOST_RUNNING. scsi_host_dev_release() shouldn't release the
parent device if host state is still SHOST_CREATED.

Link: https://lore.kernel.org/r/20210602133029.2864069-5-ming.lei@redhat.com
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Hannes Reinecke <hare@suse.de>
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Pull perf tools fixes from Arnaldo Carvalho de Melo:

- Correct buffer copying when peeking events

- Sync cpufeatures/disabled-features.h header with the kernel sources

* tag 'perf-tools-fixes-for-v5.13-2021-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
tools headers cpufeatures: Sync with the kernel sources
perf session: Correct buffer copying when peeking events

glibc complained with "The futex facility returned an unexpected error
code.". It turned out that the futex syscall returned -ERESTARTSYS because
a signal is pending. arch_do_signal_or_restart() restored the syscall
parameters (nameley regs->gprs[2]) and set PIF_SYSCALL_RESTART. When
another signal is made pending later in the exit loop
arch_do_signal_or_restart() is called again. This function clears
PIF_SYSCALL_RESTART and checks the return code which is set in
regs->gprs[2]. However, regs->gprs[2] was restored in the previous run
and no longer contains -ERESTARTSYS, so PIF_SYSCALL_RESTART isn't set
again and the syscall is skipped.

Fix this by not clearing PIF_SYSCALL_RESTART - it is already cleared in
__do_syscall() when the syscall is restarted.

Reported-by: Bjoern Walk <bwalk@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Fixes: 56e62a737028 ("s390: convert to generic entry")
Cc: <stable@vger.kernel.org> # 5.12
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Pull device properties framework fix from Rafael Wysocki:
"Fix a NULL pointer dereference introduced by a recent commit and
occurring when device_remove_software_node() is used with a device
that has never been registered (Heikki Krogerus)"

* tag 'devprop-5.13-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
software node: Handle software node injection to an existing device properly

The direction of the pipe argument must match the request-type direction
bit or control requests may fail depending on the host-controller-driver
implementation.

Control transfers without a data stage are treated as OUT requests by
the USB stack and should be using usb_sndctrlpipe(). Failing to do so
will now trigger a warning.

Fix the OSIFI2C_SET_BIT_RATE and OSIFI2C_STOP requests which erroneously
used the osif_usb_read() helper and set the IN direction bit.

Reported-by: syzbot+9d7dadd15b8819d73f41@syzkaller.appspotmail.com
Fixes: 83e53a8f120f ("i2c: Add bus driver for for OSIF USB i2c device.")
Cc: stable@vger.kernel.org # 3.14
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Dan Carpenter reported the following

The patch 0f87d9d30f21: "mm/page_alloc: add an array-based interface
to the bulk page allocator" from Apr 29, 2021, leads to the following
static checker warning:

mm/page_alloc.c:5338 __alloc_pages_bulk()
warn: potentially one past the end of array 'page_array[nr_populated]'

The problem can occur if an array is passed in that is fully populated.
That potentially ends up allocating a single page and storing it past
the end of the array. This patch returns 0 if the array is fully
populated.

Link: https://lkml.kernel.org/r/20210618125102.GU30378@techsingularity.net
Fixes: 0f87d9d30f21 ("mm/page_alloc: add an array-based interface to the bulk page allocator")
Signed-off-by: Mel Gorman <mgorman@techsinguliarity.net>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scsi_host_dev_release() only frees dev_name when host state is
SHOST_CREATED. After host state has changed to SHOST_RUNNING,
scsi_host_dev_release() no longer cleans up.

Fix this by doing a put_device(&shost->shost_dev) in the failure path when
host state is SHOST_RUNNING. Move get_device(&shost->shost_gendev) before
device_add(&shost->shost_dev) so that scsi_host_cls_release() can do a put
on this reference.

Link: https://lore.kernel.org/r/20210602133029.2864069-4-ming.lei@redhat.com
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Hannes Reinecke <hare@suse.de>
Reported-by: John Garry <john.garry@huawei.com>
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:

Stable fixes:

- Fix use-after-free in nfs4_init_client()

Bugfixes:

- Fix deadlock between nfs4_evict_inode() and nfs4_opendata_get_inode()

- Fix second deadlock in nfs4_evict_inode()

- nfs4_proc_set_acl should not change the value of NFS_CAP_UIDGID_NOMAP

- Fix setting of the NFS_CAP_SECURITY_LABEL capability"

* tag 'nfs-for-5.13-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Fix second deadlock in nfs4_evict_inode()
NFSv4: Fix deadlock between nfs4_evict_inode() and nfs4_opendata_get_inode()
NFS: FMODE_READ and friends are C macros, not enum types
NFS: Fix a potential NULL dereference in nfs_get_client()
NFS: Fix use-after-free in nfs4_init_client()
NFS: Ensure the NFS_CAP_SECURITY_LABEL capability is set when appropriate
NFSv4: nfs4_proc_set_acl needs to restore NFS_CAP_UIDGID_NOMAP on error.

To pick the changes in:

fb35d30fe5b06cc2 ("x86/cpufeatures: Assign dedicated feature word for CPUID_0x8000001F[EAX]")
e7b6385b01d8e9fb ("x86/cpufeatures: Add Intel SGX hardware bits")
1478b99a76534b6c ("x86/cpufeatures: Mark ENQCMD as disabled when configured out")

That don't cause any change in the tools, just silences this perf build
warning:

Warning: Kernel ABI header at 'tools/arch/x86/include/asm/disabled-features.h' differs from latest version at 'arch/x86/include/asm/disabled-features.h'
diff -u tools/arch/x86/include/asm/disabled-features.h arch/x86/include/asm/disabled-features.h

Cc: Borislav Petkov <bp@suse.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull xen fix from Juergen Gross:
"A fix for a regression introduced in 5.12: when migrating an irq
related to a Xen user event to another cpu, a race might result
in a WARN() triggering"

* tag 'for-linus-5.13b-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/events: reset active flag for lateeoi events later

The function software_node_notify() - the function that creates
and removes the symlinks between the node and the device - was
called unconditionally in device_add_software_node() and
device_remove_software_node(), but it needs to be called in
those functions only in the special case where the node is
added to a device that has already been registered.

This fixes NULL pointer dereference that happens if
device_remove_software_node() is used with device that was
never registered.

Fixes: b622b24519f5 ("software node: Allow node addition to already existing device")
Reported-and-tested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix Sparse warnings:
drivers/i2c/i2c-dev.c:546:19: warning: incorrect type in assignment (different address spaces)
drivers/i2c/i2c-dev.c:549:53: warning: incorrect type in argument 2 (different address spaces)

compat_ptr() returns a pointer tagged __user which gets assigned to a
pointer missing the __user annotation. The same pointer is passed to
copy_from_user() as an argument where it is expected to have the __user
annotation. Fix both by adding the __user annotation to the pointer.

Fixes: 7d5cb45655f2 ("i2c compat ioctls: move to ->compat_ioctl()")
Signed-off-by: Andreas Hecht <andreas.e.hecht@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

In the event that somebody would call this with an already fully
populated page_array, the last loop iteration would do an access beyond
the end of page_array.

It's of course extremely unlikely that would ever be done, but this
triggers my internal static analyzer. Also, if it really is not
supposed to be invoked this way (i.e., with no NULL entries in
page_array), the nr_populated<nr_pages check could simply be removed
instead.

Link: https://lkml.kernel.org/r/20210507064504.1712559-1-linux@rasmusvillemoes.dk
Fixes: 0f87d9d30f21 ("mm/page_alloc: add an array-based interface to the bulk page allocator")
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When scsi_add_host_with_dma() returns failure, the caller will call
scsi_host_put(shost) to release everything allocated for this host
instance. Consequently we can't also free allocated stuff in
scsi_add_host_with_dma(), otherwise we will end up with a double free.

Strictly speaking, host resource allocations should have been done in
scsi_host_alloc(). However, the allocations may need information which is
not yet provided by the driver when that function is called. So leave the
allocations where they are but rely on host device's release handler to
free resources.

Link: https://lore.kernel.org/r/20210602133029.2864069-3-ming.lei@redhat.com
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Hannes Reinecke <hare@suse.de>
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Pull SCSI fixes from James Bottomley:
"Four reasonably small fixes to the core for scsi host allocation
failure paths.

The root problem is that we're not freeing the memory allocated by
dev_set_name(), which involves a rejig of may of the free on error
paths to do put_device() instead of kfree which, in turn, has several
other knock on ramifications and inspection turned up a few other
lurking bugs"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: core: Only put parent device if host state differs from SHOST_CREATED
scsi: core: Put .shost_dev in failure path if host state changes to RUNNING
scsi: core: Fix failure handling of scsi_add_host_with_dma()
scsi: core: Fix error handling of scsi_host_alloc()

If the inode is being evicted but has to return a layout first, then
that too can cause a deadlock in the corner case where the server
reboots.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

When peeking an event, it has a short path and a long path. The short
path uses the session pointer "one_mmap_addr" to directly fetch the
event; and the long path needs to read out the event header and the
following event data from file and fill into the buffer pointer passed
through the argument "buf".

The issue is in the long path that it copies the event header and event
data into the same destination address which pointer "buf", this means
the event header is overwritten. We are just lucky to run into the
short path in most cases, so we don't hit the issue in the long path.

This patch adds the offset "hdr_sz" to the pointer "buf" when copying
the event data, so that it can reserve the event header which can be
used properly by its caller.

Fixes: 5a52f33adf02 ("perf session: Add perf_session__peek_event()")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210605052957.1070720-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull scheduler fix from Borislav Petkov:
"A single fix to restore fairness between control groups with equal
priority"

* tag 'sched_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Correctly insert cfs_rq's to list on unthrottle

Pull kvm fixes from Paolo Bonzini:
"A selftests fix for ARM, and the fix for page reference count
underflow. This is a very small fix that was provided by Nick Piggin
and tested by myself"

* tag 'for-linus-urgent' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: do not allow mapping valid but non-reference-counted pages
KVM: selftests: Fix mapping length truncation in m{,un}map()

In order to avoid a race condition for user events when changing
cpu affinity reset the active flag only when EOI-ing the event.

This is working fine as all user events are lateeoi events. Note that
lateeoi_ack_mask_dynirq() is not modified as there is no explicit call
to xen_irq_lateeoi() expected later.

Cc: stable@vger.kernel.org
Reported-by: Julien Grall <julien@xen.org>
Fixes: b6622798bc50b62 ("xen/events: avoid handling the same event on two cpus at the same time")
Tested-by: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrvsky@oracle.com>
Link: https://lore.kernel.org/r/20210623130913.9405-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>

We need to add a check for if the kzalloc() fails.

Fixes: 4a7695429ead ("i2c: cp2615: add i2c driver for Silicon Labs' CP2615 Digital Audio Bridge")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Bence Csókás <bence98@sch.bme.hu>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Currently me_huge_page() temporary unlocks page to perform some actions
then locks it again later. My testcase (which calls hard-offline on
some tail page in a hugetlb, then accesses the address of the hugetlb
range) showed that page allocation code detects this page lock on buddy
page and printed out "BUG: Bad page state" message.

check_new_page_bad() does not consider a page with __PG_HWPOISON as bad
page, so this flag works as kind of filter, but this filtering doesn't
work in this case because the "bad page" is not the actual hwpoisoned
page. So stop locking page again. Actions to be taken depend on the
page type of the error, so page unlocking should be done in ->action()
callbacks. So let's make it assumed and change all existing callbacks
that way.

Link: https://lkml.kernel.org/r/20210609072029.74645-1-nao.horiguchi@gmail.com
Fixes: commit 78bb920344b8 ("mm: hwpoison: dissolve in-use hugepage in unrecoverable memory error")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

After device is initialized via device_initialize(), or its name is set via
dev_set_name(), the device has to be freed via put_device(). Otherwise
device name will be leaked because it is allocated dynamically in
dev_set_name().

Fix the leak by replacing kfree() with put_device(). Since
scsi_host_dev_release() properly handles IDA and kthread removal, remove
special-casing these from the error handling as well.

Link: https://lore.kernel.org/r/20210602133029.2864069-2-ming.lei@redhat.com
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Hannes Reinecke <hare@suse.de>
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Pull RISC-V fixes from Palmer Dabbelt:

- A pair of XIP fixes: one to fix alternatives, and one to turn off the
rest of the features that require code modification

- A fix to a type that was causing some alternatives to break

- A build fix for BUILTIN_DTB

* tag 'riscv-for-linus-5.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Fix BUILTIN_DTB for sifive and microchip soc
riscv: alternative: fix typo in macro name
riscv: code patching only works on !XIP_KERNEL
riscv: xip: support runtime trap patching

If the inode is being evicted, but has to return a delegation first,
then it can cause a deadlock in the corner case where the server reboots
before the delegreturn completes, but while the call to iget5_locked() in
nfs4_opendata_get_inode() is waiting for the inode free to complete.
Since the open call still holds a session slot, the reboot recovery
cannot proceed.

In order to break the logjam, we can turn the delegation return into a
privileged operation for the case where we're evicting the inode. We
know that in that case, there can be no other state recovery operation
that conflicts.

Reported-by: zhangxiaoxu (A) <zhangxiaoxu5@huawei.com>
Fixes: 5fcdfacc01f3 ("NFSv4: Return delegations synchronously in evict_inode")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Olivier Langlois has been struggling with coredumps being incompletely written in
processes using io_uring.

Olivier Langlois <olivier@trillion01.com> writes:
> io_uring is a big user of task_work and any event that io_uring made a
> task waiting for that occurs during the core dump generation will
> generate a TIF_NOTIFY_SIGNAL.
>
> Here are the detailed steps of the problem:
> 1. io_uring calls vfs_poll() to install a task to a file wait queue
> with io_async_wake() as the wakeup function cb from io_arm_poll_handler()
> 2. wakeup function ends up calling task_work_add() with TWA_SIGNAL
> 3. task_work_add() sets the TIF_NOTIFY_SIGNAL bit by calling
> set_notify_signal()

The coredump code deliberately supports being interrupted by SIGKILL,
and depends upon prepare_signal to filter out all other signals. Now
that signal_pending includes wake ups for TIF_NOTIFY_SIGNAL this hack
in dump_emitted by the coredump code no longer works.

Make the coredump code more robust by explicitly testing for all of
the wakeup conditions the coredump code supports. This prevents
new wakeup conditions from breaking the coredump code, as well
as fixing the current issue.

The filesystem code that the coredump code uses already limits
itself to only aborting on fatal_signal_pending. So it should
not develop surprising wake-up reasons either.

v2: Don't remove the now unnecessary code in prepare_signal.

Cc: stable@vger.kernel.org
Fixes: 12db8b690010 ("entry: Add support for TIF_NOTIFY_SIGNAL")
Reported-by: Olivier Langlois <olivier@trillion01.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull irq fix from Borislav Petkov:
"A single fix for GICv3 to not take an interrupt in an NMI context"

* tag 'irq_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3: Workaround inconsistent PMR setting on NMI entry

Fix an issue where fairness is decreased since cfs_rq's can end up not
being decayed properly. For two sibling control groups with the same
priority, this can often lead to a load ratio of 99/1 (!!).

This happens because when a cfs_rq is throttled, all the descendant
cfs_rq's will be removed from the leaf list. When they initial cfs_rq
is unthrottled, it will currently only re add descendant cfs_rq's if
they have one or more entities enqueued. This is not a perfect
heuristic.

Instead, we insert all cfs_rq's that contain one or more enqueued
entities, or it its load is not completely decayed.

Can often lead to situations like this for equally weighted control
groups:

$ ps u -C stress
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 10009 88.8 0.0 3676 100 pts/1 R+ 11:04 0:13 stress --cpu 1
root 10023 3.0 0.0 3676 104 pts/1 R+ 11:04 0:00 stress --cpu 1

Fixes: 31bc6aeaab1d ("sched/fair: Optimize update_blocked_averages()")
[vingo: !SMP build fix]
Signed-off-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20210612112815.61678-1-odin@uged.al

Pull x86 fixes from Borislav Petkov:
"Two more urgent FPU fixes:

- prevent unprivileged userspace from reinitializing supervisor
states

- prepare init_fpstate, which is the buffer used when initializing
FPU state, properly in case the skip-writing-state-components
XSAVE* variants are used"

* tag 'x86_urgent_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Make init_fpstate correct with optimized XSAVE
x86/fpu: Preserve supervisor states in sanitize_restored_user_xstate()

It's possible to create a region which maps valid but non-refcounted
pages (e.g., tail pages of non-compound higher order allocations). These
host pages can then be returned by gfn_to_page, gfn_to_pfn, etc., family
of APIs, which take a reference to the page, which takes it from 0 to 1.
When the reference is dropped, this will free the page incorrectly.

Fix this by only taking a reference on valid pages if it was non-zero,
which indicates it is participating in normal refcounting (and can be
released with put_page).

This addresses CVE-2021-22543.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Do this in order to prevent the task from being freed if the thread
returns (which can be triggered by the frontend) before the call to
kthread_stop done as part of the backend tear down. Not taking the
reference will lead to a use-after-free in that scenario. Such
reference was taken before but dropped as part of the rework done in
2ac061ce97f4.

Reintroduce the reference taking and add a comment this time
explaining why it's needed.

This is XSA-374 / CVE-2021-28691.

Fixes: 2ac061ce97f4 ('xen/netback: cleanup init and deinit code')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

As explained in [0] currently we may leave SMBHSTSTS_INUSE_STS set,
thus potentially breaking ACPI/BIOS usage of the SMBUS device.

Seems patch [0] needs a little bit more of review effort, therefore
I'd suggest to apply a part of it as quick win. Just clearing
SMBHSTSTS_INUSE_STS when leaving i801_access() should fix the
referenced issue and leaves more time for discussing a more
sophisticated locking handling.

[0] https://www.spinics.net/lists/linux-i2c/msg51558.html

Fixes: 01590f361e94 ("i2c: i801: Instantiate SPD EEPROMs automatically")
Suggested-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Hector Martin <marcan@marcan.st>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

When memory_failure() is called with MF_ACTION_REQUIRED on the page that
has already been hwpoisoned, memory_failure() could fail to send SIGBUS
to the affected process, which results in infinite loop of MCEs.

Currently memory_failure() returns 0 if it's called for already
hwpoisoned page, then the caller, kill_me_maybe(), could return without
sending SIGBUS to current process. An action required MCE is raised
when the current process accesses to the broken memory, so no SIGBUS
means that the current process continues to run and access to the error
page again soon, so running into MCE loop.

This issue can arise for example in the following scenarios:

- Two or more threads access to the poisoned page concurrently. If
local MCE is enabled, MCE handler independently handles the MCE
events. So there's a race among MCE events, and the second or latter
threads fall into the situation in question.

- If there was a precedent memory error event and memory_failure() for
the event failed to unmap the error page for some reason, the
subsequent memory access to the error page triggers the MCE loop
situation.

To fix the issue, make memory_failure() return an error code when the
error page has already been hwpoisoned. This allows memory error
handler to control how it sends signals to userspace. And make sure
that any process touching a hwpoisoned page should get a SIGBUS even in
"already hwpoisoned" path of memory_failure() as is done in page fault
path.

Link: https://lkml.kernel.org/r/20210521030156.2612074-3-nao.horiguchi@gmail.com
Signed-off-by: Aili Yao <yaoaili@kingsoft.com>
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jue Wang <juew@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Apparently some arrays are now returning "HPE" as the vendor.

Link: https://lore.kernel.org/r/20210601175214.25719-1-emilne@redhat.com
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

0day robot reported a 9.2% regression for will-it-scale mmap1 test
case[1], caused by commit 57efa1fe5957 ("mm/gup: prevent gup_fast from
racing with COW during fork").

Further debug shows the regression is due to that commit changes the
offset of hot fields 'mmap_lock' inside structure 'mm_struct', thus some
cache alignment changes.

From the perf data, the contention for 'mmap_lock' is very severe and
takes around 95% cpu cycles, and it is a rw_semaphore

struct rw_semaphore {
atomic_long_t count; /* 8 bytes */
atomic_long_t owner; /* 8 bytes */
struct optimistic_spin_queue osq; /* spinner MCS lock */
...

Before commit 57efa1fe5957 adds the 'write_protect_seq', it happens to
have a very optimal cache alignment layout, as Linus explained:

"and before the addition of the 'write_protect_seq' field, the
mmap_sem was at offset 120 in 'struct mm_struct'.

Which meant that count and owner were in two different cachelines,
and then when you have contention and spend time in
rwsem_down_write_slowpath(), this is probably *exactly* the kind
of layout you want.

Because first the rwsem_write_trylock() will do a cmpxchg on the
first cacheline (for the optimistic fast-path), and then in the
case of contention, rwsem_down_write_slowpath() will just access
the second cacheline.

Which is probably just optimal for a load that spends a lot of
time contended - new waiters touch that first cacheline, and then
they queue themselves up on the second cacheline."

After the commit, the rw_semaphore is at offset 128, which means the
'count' and 'owner' fields are now in the same cacheline, and causes
more cache bouncing.

Currently there are 3 "#ifdef CONFIG_XXX" before 'mmap_lock' which will
affect its offset:

CONFIG_MMU
CONFIG_MEMBARRIER
CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES

The layout above is on 64 bits system with 0day's default kernel config
(similar to RHEL-8.3's config), in which all these 3 options are 'y'.
And the layout can vary with different kernel configs.

Relayouting a structure is usually a double-edged sword, as sometimes it
can helps one case, but hurt other cases. For this case, one solution
is, as the newly added 'write_protect_seq' is a 4 bytes long seqcount_t
(when CONFIG_DEBUG_LOCK_ALLOC=n), placing it into an existing 4 bytes
hole in 'mm_struct' will not change other fields' alignment, while
restoring the regression.

Link: https://lore.kernel.org/lkml/20210525031636.GB7744@xsang-OptiPlex-9020/ [1]
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix BUILTIN_DTB config which resulted in a dtb that was actually not
built into the Linux image: in the same manner as Canaan soc does,
create an object file from the dtb file that will get linked into the
Linux image.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

Address a sparse warning:

CHECK fs/nfs/nfstrace.c
fs/nfs/nfstrace.c: note: in included file (through /home/cel/src/linux/rpc-over-tls/include/trace/trace_events.h, /home/cel/src/linux/rpc-over-tls/include/trace/define_trace.h, ...):
fs/nfs/./nfstrace.h:424:1: warning: incorrect type in initializer (different base types)
fs/nfs/./nfstrace.h:424:1: expected unsigned long eval_value
fs/nfs/./nfstrace.h:424:1: got restricted fmode_t [usertype]
fs/nfs/./nfstrace.h:425:1: warning: incorrect type in initializer (different base types)
fs/nfs/./nfstrace.h:425:1: expected unsigned long eval_value
fs/nfs/./nfstrace.h:425:1: got restricted fmode_t [usertype]
fs/nfs/./nfstrace.h:426:1: warning: incorrect type in initializer (different base types)
fs/nfs/./nfstrace.h:426:1: expected unsigned long eval_value
fs/nfs/./nfstrace.h:426:1: got restricted fmode_t [usertype]

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Pull cgroup fix from Tejun Heo:
"This is a high priority but low risk fix for a cgroup1 bug where
rename(2) can change a cgroup's name to something which can break
parsing of /proc/PID/cgroup"

* 'for-5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup1: don't allow '\n' in renaming

Pull x86 fixes from Borislav Petkov:
"A first set of urgent fixes to the FPU/XSTATE handling mess^W code.
(There's a lot more in the pipe):

- Prevent corruption of the XSTATE buffer in signal handling by
validating what is being copied from userspace first.

- Invalidate other task's preserved FPU registers on XRSTOR failure
(#PF) because latter can still modify some of them.

- Restore the proper PKRU value in case userspace modified it

- Reset FPU state when signal restoring fails

Other:

- Map EFI boot services data memory as encrypted in a SEV guest so
that the guest can access it and actually boot properly

- Two SGX correctness fixes: proper resources freeing and a NUMA fix"

* tag 'x86_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Avoid truncating memblocks for SGX memory
x86/sgx: Add missing xa_destroy() when virtual EPC is destroyed
x86/fpu: Reset state for all signal restore failures
x86/pkru: Write hardware init value to PKRU when xstate is init
x86/process: Check PF_KTHREAD and not current->mm for kernel threads
x86/fpu: Invalidate FPU state after a failed XRSTOR from a user buffer
x86/fpu: Prevent state corruption in __fpu__restore_sig()
x86/ioremap: Map EFI-reserved memory as encrypted for SEV