Originally, I was convinced that we needed to use tmpalias flushes
everwhere, for both user and kernel flushes. However, when I modified
flush_kernel_dcache_page_addr, to use a tmpalias flush, my c8000
would crash quite early when booting.
The PDC returns alias values of 0 for the icache and dcache. This
indicates that either the alias boundary is greater than 16MB or
equivalent aliasing doesn't work. I modified the tmpalias code to
make it easy to try alternate boundaries. I tried boundaries up to
128MB but still kernel tmpalias flushes didn't work on c8000.
This led me to conclude that tmpalias flushes don't work on PA8800
and PA8900 machines, and that we needed to flush directly using the
virtual address of user and kernel pages. This is likely the major
cause of instability on the c8000 and rp34xx machines.
Flushing user pages requires doing a temporary context switch as we
have to flush pages that don't belong to the current context. Further,
we have to deal with pages that aren't present. If a page isn't
present, the flush instructions fault on every line.
Other code has been rearranged and simplified based on testing. For
example, I introduced a flush_cache_dup_mm routine. flush_cache_mm
and flush_cache_dup_mm differ in that flush_cache_mm calls
purge_cache_pages and flush_cache_dup_mm calls flush_cache_pages.
In some implementations, pdc is more efficient than fdc. Based on
my testing, I don't believe there's any performance benefit on the
c8000.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Change the "BUG" to "WARNING" and disable the message because it triggers
occasionally in spite of the check in flush_cache_page_if_present.
The pte value extracted for the "from" page in copy_user_highpage is racy and
occasionally the pte is cleared before the flush is complete. I assume that
the page is simultaneously flushed by flush_cache_mm before the pte is cleared
as nullifying the fdc doesn't seem to cause problems.
I investigated various locking scenarios but I wasn't able to find a way to
sequence the flushes. This code is called for every COW break and locks impact
performance.
This patch is related to the bigger cache flush patch because we need the pte
on PA8800/PA8900 to flush using the vma context.
I have also seen this from copy_to_user_page and copy_from_user_page.
The messages appear infrequently when enabled.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Pull driver core fixes from Greg KH:
"Here is one fix, and three documentation updates for 5.18-rc7.
The fix is for the firmware loader which resolves a long-reported
problem where the credentials of the firmware loader could be set to a
userspace process without enough permissions to actually load the
firmware image. Many Android vendors have been reporting this for
quite some time.
The documentation updates are for the embargoed-hardware-issues.rst
file to add a new entry, change an existing one, and sort the list to
make changes easier in the future.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
Documentation/process: Update ARM contact for embargoed hardware issues
Documentation/process: Add embargoed HW contact for Ampere Computing
Documentation/process: Make groups alphabetical and use tabs consistently
firmware_loader: use kernel credentials when reading firmware
Pull char/misc driver fixes from Greg KH:
"Here are two small driver fixes for 5.18-rc7 that resolve reported
problems:
- slimbus driver irq bugfix
- interconnect sync state bugfix
Both of these have been in linux-next with no reported problems"
* tag 'char-misc-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
slimbus: qcom: Fix IRQ check in qcom_slim_probe
interconnect: Restore sync state by ignoring ipa-virt in provider count
Pull tty/serial driver fixes from Greg KH:
"Here are some small tty n_gsm and serial driver fixes for 5.18-rc7
that resolve reported problems. They include:
- n_gsm fixes for reported issues
- 8250_mtk driver fixes for some platforms
- fsl_lpuart driver fix for reported problem.
- digicolor driver fix for reported problem.
All have been in linux-next for a while with no reported problems"
* tag 'tty-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
fsl_lpuart: Don't enable interrupts too early
tty: n_gsm: fix invalid gsmtty_write_room() result
tty: n_gsm: fix mux activation issues in gsm_config()
tty: n_gsm: fix buffer over-read in gsm_dlci_data()
serial: 8250_mtk: Fix register address for XON/XOFF character
serial: 8250_mtk: Make sure to select the right FEATURE_SEL
serial: 8250_mtk: Fix UART_EFR register address
tty/serial: digicolor: fix possible null-ptr-deref in digicolor_uart_probe()
Pull USB fixes from Greg KH:
"Here are some small fixes for reported issues with some USB drivers.
They include:
- xhci fixes for xhci-mtk platform driver
- typec driver fixes for reported problems.
- cdc-wdm read-stuck fix
- gadget driver fix for reported race condition
- new usb-serial driver ids
All of these have been in linux-next with no reported problems"
* tag 'usb-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: xhci-mtk: remove bandwidth budget table
usb: xhci-mtk: fix fs isoc's transfer error
usb: gadget: fix race when gadget driver register via ioctl
usb: typec: tcpci_mt6360: Update for BMC PHY setting
usb: gadget: uvc: allow for application to cleanly shutdown
usb: typec: tcpci: Don't skip cleanup in .remove() on error
usb: cdc-wdm: fix reading stuck on device close
USB: serial: qcserial: add support for Sierra Wireless EM7590
USB: serial: option: add Fibocom MA510 modem
USB: serial: option: add Fibocom L610 modem
USB: serial: pl2303: add device id for HP LM930 Display
Pull powerpc fix from Michael Ellerman:
- Fix KVM PR on 32-bit, which was broken by some MMU code refactoring.
Thanks to: Alexander Graf, and Matt Evans.
* tag 'powerpc-5.18-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
KVM: PPC: Book3S PR: Enable MSR_DR for switch_mmu_context()
Pull x86 fix from Thomas Gleixner:
"A single fix for the handling of unpopulated sub-pmd spaces.
The copy & pasta from the corresponding s390 code screwed up the
address calculation for marking the sub-pmd ranges via memset by
omitting the ALIGN_DOWN() to calculate the proper start address.
It's a mystery why this code is not generic and shared because there
is nothing architecture specific in there, but that's too intrusive
for a backportable fix"
* tag 'x86-urgent-2022-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix marking of unused sub-pmd ranges
Pull scheduler fix from Thomas Gleixner:
"The recent expansion of the sched switch tracepoint inserted a new
argument in the middle of the arguments. This reordering broke BPF
programs which relied on the old argument list.
While tracepoints are not considered stable ABI, it's not trivial to
make BPF cope with such a change, but it's being worked on. For now
restore the original argument order and move the new argument to the
end of the argument list"
* tag 'sched-urgent-2022-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/tracing: Append prev_state to tp args instead
Pull irq fix from Thomas Gleixner:
"A single fix for a recent (introduced in 5.16) regression in the core
interrupt code.
The consolidation of the interrupt handler invocation code added an
unconditional warning when generic_handle_domain_irq() is invoked from
outside hard interrupt context. That's overbroad as the requirement
for invoking these handlers in hard interrupt context is only required
for certain interrupt types. The subsequently called code already
contains a warning which triggers conditionally for interrupt chips
which indicate this requirement in their properties.
Remove the overbroad one"
* tag 'irq-urgent-2022-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Remove WARN_ON_ONCE() in generic_handle_domain_irq()
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix two NDEBUG warnings in 'perf bench numa'
- Fix ARM coresight `perf test` failure
- Sync linux/kvm.h with the kernel sources
- Add James and Mike as Arm64 performance events reviewers
* tag 'perf-tools-fixes-for-v5.18-2022-05-14' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
MAINTAINERS: Add James and Mike as Arm64 performance events reviewers
tools headers UAPI: Sync linux/kvm.h with the kernel sources
perf tests: Fix coresight `perf test` failure.
perf bench: Fix two numa NDEBUG warnings
Pull more drm fixes from Dave Airlie:
"Turns out I was right, some fixes hadn't made it to me yet. The vmwgfx
ones also popped up later, but all seem like bad enough things to fix.
The dma-buf, vc4 and nouveau ones are all pretty small.
The fbdev fixes are a bit more complicated: a fix to cleanup fbdev
devices properly, uncovered some use-after-free bugs in existing
drivers. Then the fix for those bugs wasn't correct. This reverts that
fix, and puts the proper fixes in place in the drivers to avoid the
use-after-frees.
This has had a fair number of eyes on it at this stage, and I'm
confident enough that it puts things in the right place, and is less
dangerous than reverting our way out of the initial change at this
stage.
fbdev:
- revert NULL deref fix that turned into a use-after-free
- prevent use-after-free in fbdev
- efifb/simplefb/vesafb: fix cleanup paths to avoid use-after-frees
dma-buf:
- fix panic in stats setup
vc4:
- fix hdmi build
nouveau:
- tegra iommu present fix
- fix leak in backlight name
vmwgfx:
- Black screen due to fences using FIFO checks on SVGA3
- Random black screens on boot due to uninitialized drm_mode_fb_cmd2
- Hangs on SVGA3 due to command buffers being used with gbobjects"
* tag 'drm-fixes-2022-05-14' of git://anongit.freedesktop.org/drm/drm:
drm/vmwgfx: Disable command buffers on svga3 without gbobjects
drm/vmwgfx: Initialize drm_mode_fb_cmd2
drm/vmwgfx: Fix fencing on SVGAv3
drm/vc4: hdmi: Fix build error for implicit function declaration
dma-buf: call dma_buf_stats_setup after dmabuf is in valid list
fbdev: efifb: Fix a use-after-free due early fb_info cleanup
drm/nouveau: Fix a potential theorical leak in nouveau_get_backlight_name()
drm/nouveau/tegra: Stop using iommu_present()
fbdev: vesafb: Cleanup fb_info in .fb_destroy rather than .remove
fbdev: efifb: Cleanup fb_info in .fb_destroy rather than .remove
fbdev: simplefb: Cleanup fb_info in .fb_destroy rather than .remove
fbdev: Prevent possible use-after-free in fb_release()
Revert "fbdev: Make fb_release() return -ENODEV if fbdev was unregistered"
Pull gfs2 fixes from Andreas Gruenbacher:
"We've finally identified commit dc732906c2 ("gfs2: Introduce flag
for glock holder auto-demotion") to be the other cause of the
filesystem corruption we've been seeing. This feature isn't strictly
necessary anymore, so we've decided to stop using it for now.
With this and the gfs_iomap_end rounding fix you've already seen
("gfs2: Fix filesystem block deallocation for short writes" in this
pull request), we're corruption free again now.
- Fix filesystem block deallocation for short writes.
- Stop using glock holder auto-demotion for now.
- Get rid of buffered writes inefficiencies due to page faults being
disabled.
- Minor other cleanups"
* tag 'gfs2-v5.18-rc4-fix3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Stop using glock holder auto-demotion for now
gfs2: buffered write prefaulting
gfs2: Align read and write chunks to the page cache
gfs2: Pull return value test out of should_fault_in_pages
gfs2: Clean up use of fault_in_iov_iter_{read,write}able
gfs2: Variable rename
gfs2: Fix filesystem block deallocation for short writes
We're having unresolved issues with the glock holder auto-demotion mechanism
introduced in commit dc732906c2. This mechanism was assumed to be essential
for avoiding frequent short reads and writes until commit 296abc0d91
("gfs2: No short reads or writes upon glock contention"). Since then,
when the inode glock is lost, it is simply re-acquired and the operation
is resumed. This means that apart from the performance penalty, we
might as well drop the inode glock before faulting in pages, and
re-acquire it afterwards.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In gfs2_file_buffered_write, to increase the likelihood that all the
user memory we're trying to write will be resident in memory, carry out
the write in chunks and fault in each chunk of user memory before trying
to write it. Otherwise, some workloads will trigger frequent short
"internal" writes, causing filesystem blocks to be allocated and then
partially deallocated again when writing into holes, which is wasteful
and breaks reservations.
Neither the chunked writes nor any of the short "internal" writes are
user visible.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Pull SCSI fixes from James Bottomley:
"Four fixes, all in drivers.
These patches mosly fix error legs and exceptional conditions
(scsi_dh_alua, qla2xxx). The lpfc fixes are for coding issues with
lpfc features"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: lpfc: Correct BDE DMA address assignment for GEN_REQ_WQE
scsi: lpfc: Fix split code for FLOGI on FCoE
scsi: qla2xxx: Fix missed DMA unmap for aborted commands
scsi: scsi_dh_alua: Properly handle the ALUA transitioning state
Align the chunks that reads and writes are carried out in to the page
cache rather than the user buffers. This will be more efficient in
general, especially for allocating writes. Optimizing the case that the
user buffer is gfs2 backed isn't very useful; we only need to make sure
we won't deadlock.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Pull the return value test of the previous read or write operation out
of should_fault_in_pages(). In a following patch, we'll fault in pages
before the I/O and there will be no return value to check.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Instead of counting the number of bytes read from the filesystem,
functions gfs2_file_direct_read and gfs2_file_read_iter count the number
of bytes written into the user buffer. Conversely, functions
gfs2_file_direct_write and gfs2_file_buffered_write count the number of
bytes read from the user buffer. This is nothing but confusing, so
change the read functions to count how many bytes they have read, and
the write functions to count how many bytes they have written.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When a write cannot be carried out in full, gfs2_iomap_end() releases
blocks that have been allocated for this write but haven't been used.
To compute the end of the allocation, gfs2_iomap_end() incorrectly
rounded the end of the attempted write down to the next block boundary
to arrive at the end of the allocation. It would have to round up, but
the end of the allocation is also available as iomap->offset +
iomap->length, so just use that instead.
In addition, use round_up() for computing the start of the unused range.
Fixes: 64bc06bb32 ("gfs2: iomap buffered write support")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Pull ceph fix from Ilya Dryomov:
"Two fixes to properly maintain xattrs on async creates and thus
preserve SELinux context on newly created files and to avoid improper
usage of folio->private field which triggered BUG_ONs.
Both marked for stable"
* tag 'ceph-for-5.18-rc7' of https://github.com/ceph/ceph-client:
ceph: check folio PG_private bit instead of folio->private
ceph: fix setting of xattrs on async created inodes
