Doing a "get_user_pages()" on a copy-on-write page for reading can be
ambiguous: the page can be COW'ed at any time afterwards, and the
direction of a COW event isn't defined.
Yes, whoever writes to it will generally do the COW, but if the thread
that did the get_user_pages() unmapped the page before the write (and
that could happen due to memory pressure in addition to any outright
action), the writer could also just take over the old page instead.
End result: the get_user_pages() call might result in a page pointer
that is no longer associated with the original VM, and is associated
with - and controlled by - another VM having taken it over instead.
So when doing a get_user_pages() on a COW mapping, the only really safe
thing to do would be to break the COW when getting the page, even when
only getting it for reading.
At the same time, some users simply don't even care.
For example, the perf code wants to look up the page not because it
cares about the page, but because the code simply wants to look up the
physical address of the access for informational purposes, and doesn't
really care about races when a page might be unmapped and remapped
elsewhere.
This adds logic to force a COW event by setting FOLL_WRITE on any
copy-on-write mapping when FOLL_GET (or FOLL_PIN) is used to get a page
pointer as a result.
The current semantics end up being:
- __get_user_pages_fast(): no change. If you don't ask for a write,
you won't break COW. You'd better know what you're doing.
- get_user_pages_fast(): the fast-case "look it up in the page tables
without anything getting mmap_sem" now refuses to follow a read-only
page, since it might need COW breaking. Which happens in the slow
path - the fast path doesn't know if the memory might be COW or not.
- get_user_pages() (including the slow-path fallback for gup_fast()):
for a COW mapping, turn on FOLL_WRITE for FOLL_GET/FOLL_PIN, with
very similar semantics to FOLL_FORCE.
If it turns out that we want finer granularity (ie "only break COW when
it might actually matter" - things like the zero page are special and
don't need to be broken) we might need to push these semantics deeper
into the lookup fault path. So if people care enough, it's possible
that we might end up adding a new internal FOLL_BREAK_COW flag to go
with the internal FOLL_COW flag we already have for tracking "I had a
COW".
Alternatively, if it turns out that different callers might want to
explicitly control the forced COW break behavior, we might even want to
make such a flag visible to the users of get_user_pages() instead of
using the above default semantics.
But for now, this is mostly commentary on the issue (this commit message
being a lot bigger than the patch, and that patch in turn is almost all
comments), with that minimal "enable COW breaking early" logic using the
existing FOLL_WRITE behavior.
[ It might be worth noting that we've always had this ambiguity, and it
could arguably be seen as a user-space issue.
You only get private COW mappings that could break either way in
situations where user space is doing cooperative things (ie fork()
before an execve() etc), but it _is_ surprising and very subtle, and
fork() is supposed to give you independent address spaces.
So let's treat this as a kernel issue and make the semantics of
get_user_pages() easier to understand. Note that obviously a true
shared mapping will still get a page that can change under us, so this
does _not_ mean that get_user_pages() somehow returns any "stable"
page ]
Reported-by: Jann Horn <jannh@google.com>
Tested-by: Christoph Hellwig <hch@lst.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kirill Shutemov <kirill@shutemov.name>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull uaccess/readdir updates from Al Viro:
"Finishing the conversion of readdir.c to unsafe_... API.
This includes the uaccess_{read,write}_begin series by Christophe
Leroy"
* 'uaccess.readdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
readdir.c: get rid of the last __put_user(), drop now-useless access_ok()
readdir.c: get compat_filldir() more or less in sync with filldir()
switch readdir(2) to unsafe_copy_dirent_name()
drm/i915/gem: Replace user_access_begin by user_write_access_begin
uaccess: Selectively open read or write user access
uaccess: Add user_read_access_begin/end and user_write_access_begin/end
Pull uaccess/access_ok updates from Al Viro:
"Removals of trivially pointless access_ok() calls.
Note: the fiemap stuff was removed from the series, since they are
duplicates with part of ext4 series carried in Ted's tree"
* 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vmci_host: get rid of pointless access_ok()
hfi1: get rid of pointless access_ok()
usb: get rid of pointless access_ok() calls
lpfc_debugfs: get rid of pointless access_ok()
efi_test: get rid of pointless access_ok()
drm_read(): get rid of pointless access_ok()
via-pmu: don't bother with access_ok()
drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok()
omapfb: get rid of pointless access_ok() calls
amifb: get rid of pointless access_ok() calls
drivers/fpga/dfl-afu-dma-region.c: get rid of pointless access_ok()
drivers/fpga/dfl-fme-pr.c: get rid of pointless access_ok()
cm4000_cs.c cmm_ioctl(): get rid of pointless access_ok()
nvram: drop useless access_ok()
n_hdlc_tty_read(): remove pointless access_ok()
tomoyo_write_control(): get rid of pointless access_ok()
btrfs_ioctl_send(): don't bother with access_ok()
fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade...
dlmfs_file_write(): get rid of pointless access_ok()
set from Mauro toward the completion of the RST conversion. I *really*
hope we are getting close to the end of this. Meanwhile, those patches
reach pretty far afield to update document references around the tree;
there should be no actual code changes there. There will be, alas, more of
the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots of
fixes.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl7VId8PHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5Yq/gH/iaDgirQZV6UZ2v9sfwQNYolNpf2sKAuOZjd
bPFB7WJoMQbKwQEvYrAUL2+5zPOcLYuIfzyOfo1BV1py+EyKbACcKjI4AedxfJF7
+NchmOBhlEqmEhzx2U08HRc4/8J223WG17fJRVsV3p+opJySexSFeQucfOciX5NR
RUCxweWWyg/FgyqjkyMMTtsePqZPmcT5dWTlVXISlbWzcv5NFhuJXnSrw8Sfzcmm
SJMzqItv3O+CabnKQ8kMLV2PozXTMfjeWH47ZUK0Y8/8PP9+cvqwFzZ0UDQJ1Xaz
oyW/TqmunaXhfMsMFeFGSwtfgwRHvXdxkQdtwNHvo1dV4dzTvDw=
=fDC/
-----END PGP SIGNATURE-----
Merge tag 'docs-5.8' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"
* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
...
- remove a now unnecessary usage of the KERNEL_DS for
sys_oabi_epoll_ctl()
- update my email address in a number of drivers
- decompressor EFI updates from Ard Biesheuvel
- module unwind section handling updates
- sparsemem Kconfig cleanups
- make act_mm macro respect THREAD_SIZE
-----BEGIN PGP SIGNATURE-----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=vMHE
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
- remove a now unnecessary usage of the KERNEL_DS for
sys_oabi_epoll_ctl()
- update my email address in a number of drivers
- decompressor EFI updates from Ard Biesheuvel
- module unwind section handling updates
- sparsemem Kconfig cleanups
- make act_mm macro respect THREAD_SIZE
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8980/1: Allow either FLATMEM or SPARSEMEM on the multiplatform build
ARM: 8979/1: Remove redundant ARCH_SPARSEMEM_DEFAULT setting
ARM: 8978/1: mm: make act_mm() respect THREAD_SIZE
ARM: decompressor: run decompressor in place if loaded via UEFI
ARM: decompressor: move GOT into .data for EFI enabled builds
ARM: decompressor: defer loading of the contents of the LC0 structure
ARM: decompressor: split off _edata and stack base into separate object
ARM: decompressor: move headroom variable out of LC0
ARM: 8976/1: module: allow arch overrides for .init section names
ARM: 8975/1: module: fix handling of unwind init sections
ARM: 8974/1: use SPARSMEM_STATIC when SPARSEMEM is enabled
ARM: 8971/1: replace the sole use of a symbol with its definition
ARM: 8969/1: decompressor: simplify libfdt builds
Update rmk's email address in various drivers
ARM: compat: remove KERNEL_DS usage in sys_oabi_epoll_ctl()
- Add AMD Fam17h RAPL support
- Introduce CAP_PERFMON to kernel and user space
- Add Zhaoxin CPU support
- Misc fixes and cleanups
Tooling changes:
perf record:
- Introduce --switch-output-event to use arbitrary events to be setup
and read from a side band thread and, when they take place a signal
be sent to the main 'perf record' thread, reusing the --switch-output
code to take perf.data snapshots from the --overwrite ring buffer, e.g.:
# perf record --overwrite -e sched:* \
--switch-output-event syscalls:*connect* \
workload
will take perf.data.YYYYMMDDHHMMSS snapshots up to around the
connect syscalls.
- Add --num-synthesize-threads option to control degree of parallelism of the
synthesize_mmap() code which is scanning /proc/PID/task/PID/maps and can be
time consuming. This mimics pre-existing behaviour in 'perf top'.
perf bench:
- Add a multi-threaded synthesize benchmark.
- Add kallsyms parsing benchmark.
Intel PT support:
- Stitch LBR records from multiple samples to get deeper backtraces,
there are caveats, see the csets for details.
- Allow using Intel PT to synthesize callchains for regular events.
- Add support for synthesizing branch stacks for regular events (cycles,
instructions, etc) from Intel PT data.
Misc changes:
- Updated perf vendor events for power9 and Coresight.
- Add flamegraph.py script via 'perf flamegraph'
- Misc other changes, fixes and cleanups - see the Git log for details.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=i27M
-----END PGP SIGNATURE-----
Merge tag 'perf-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
"Kernel side changes:
- Add AMD Fam17h RAPL support
- Introduce CAP_PERFMON to kernel and user space
- Add Zhaoxin CPU support
- Misc fixes and cleanups
Tooling changes:
- perf record:
Introduce '--switch-output-event' to use arbitrary events to be
setup and read from a side band thread and, when they take place a
signal be sent to the main 'perf record' thread, reusing the core
for '--switch-output' to take perf.data snapshots from the ring
buffer used for '--overwrite', e.g.:
# perf record --overwrite -e sched:* \
--switch-output-event syscalls:*connect* \
workload
will take perf.data.YYYYMMDDHHMMSS snapshots up to around the
connect syscalls.
Add '--num-synthesize-threads' option to control degree of
parallelism of the synthesize_mmap() code which is scanning
/proc/PID/task/PID/maps and can be time consuming. This mimics
pre-existing behaviour in 'perf top'.
- perf bench:
Add a multi-threaded synthesize benchmark and kallsyms parsing
benchmark.
- Intel PT support:
Stitch LBR records from multiple samples to get deeper backtraces,
there are caveats, see the csets for details.
Allow using Intel PT to synthesize callchains for regular events.
Add support for synthesizing branch stacks for regular events
(cycles, instructions, etc) from Intel PT data.
Misc changes:
- Updated perf vendor events for power9 and Coresight.
- Add flamegraph.py script via 'perf flamegraph'
- Misc other changes, fixes and cleanups - see the Git log for details
Also, since over the last couple of years perf tooling has matured and
decoupled from the kernel perf changes to a large degree, going
forward Arnaldo is going to send perf tooling changes via direct pull
requests"
* tag 'perf-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (163 commits)
perf/x86/rapl: Add AMD Fam17h RAPL support
perf/x86/rapl: Make perf_probe_msr() more robust and flexible
perf/x86/rapl: Flip logic on default events visibility
perf/x86/rapl: Refactor to share the RAPL code between Intel and AMD CPUs
perf/x86/rapl: Move RAPL support to common x86 code
perf/core: Replace zero-length array with flexible-array
perf/x86: Replace zero-length array with flexible-array
perf/x86/intel: Add more available bits for OFFCORE_RESPONSE of Intel Tremont
perf/x86/rapl: Add Ice Lake RAPL support
perf flamegraph: Use /bin/bash for report and record scripts
perf cs-etm: Move definition of 'traceid_list' global variable from header file
libsymbols kallsyms: Move hex2u64 out of header
libsymbols kallsyms: Parse using io api
perf bench: Add kallsyms parsing
perf: cs-etm: Update to build with latest opencsd version.
perf symbol: Fix kernel symbol address display
perf inject: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*()
perf annotate: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*()
perf trace: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*()
perf script: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*()
...
- RCU-tasks update, including addition of RCU Tasks Trace for
BPF use and TASKS_RUDE_RCU
- kfree_rcu() updates.
- Remove scheduler locking restriction
- RCU CPU stall warning updates.
- Torture-test updates.
- Miscellaneous fixes and other updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Yisx
-----END PGP SIGNATURE-----
Merge tag 'core-rcu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
"The RCU updates for this cycle were:
- RCU-tasks update, including addition of RCU Tasks Trace for BPF use
and TASKS_RUDE_RCU
- kfree_rcu() updates.
- Remove scheduler locking restriction
- RCU CPU stall warning updates.
- Torture-test updates.
- Miscellaneous fixes and other updates"
* tag 'core-rcu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
rcu: Allow for smp_call_function() running callbacks from idle
rcu: Provide rcu_irq_exit_check_preempt()
rcu: Abstract out rcu_irq_enter_check_tick() from rcu_nmi_enter()
rcu: Provide __rcu_is_watching()
rcu: Provide rcu_irq_exit_preempt()
rcu: Make RCU IRQ enter/exit functions rely on in_nmi()
rcu/tree: Mark the idle relevant functions noinstr
x86: Replace ist_enter() with nmi_enter()
x86/mce: Send #MC singal from task work
x86/entry: Get rid of ist_begin/end_non_atomic()
sched,rcu,tracing: Avoid tracing before in_nmi() is correct
sh/ftrace: Move arch_ftrace_nmi_{enter,exit} into nmi exception
lockdep: Always inline lockdep_{off,on}()
hardirq/nmi: Allow nested nmi_enter()
arm64: Prepare arch_nmi_enter() for recursion
printk: Disallow instrumenting print_nmi_enter()
printk: Prepare for nested printk_nmi_enter()
rcutorture: Convert ULONG_CMP_LT() to time_before()
torture: Add a --kasan argument
torture: Save a few lines by using config_override_param initially
...
comparison
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCXs+b2wAKCRDj7w1vZxhR
xdZ9AQC9uquqrOAGV8Falzp+Obu1MDp7nu8zrKH35jWt+UtONwEAk8TsnMAq7y18
Bi4cAke59vX/YLiMaN8EamJs67FGsw0=
=zcXf
-----END PGP SIGNATURE-----
Merge tag 'drm-misc-fixes-2020-05-28' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Two ingenic fixes, one for a wrong cast, the other for a typo in a
comparison
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200528110944.hanv4qgc6w7whnj3@gilmour.lan
[Why]
If VUPDATE_END is before VUPDATE_START the delay calculated can become
very large, causing a soft hang.
[How]
Take the absolute value of the difference between START and END.
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
get_cursor_position already handles the case where the cursor has
negative off-screen coordinates by not setting
dc_cursor_position.enabled.
Signed-off-by: Simon Ser <contact@emersion.fr>
Fixes: 626bf90fe0 ("drm/amd/display: add basic atomic check for cursor plane")
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Pull cgroup fixes from Tejun Heo:
- Reverted stricter synchronization for cgroup recursive stats which
was prepping it for event counter usage which never got merged. The
change was causing performation regressions in some cases.
- Restore bpf-based device-cgroup operation even when cgroup1 device
cgroup is disabled.
- An out-param init fix.
* 'for-5.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
device_cgroup: Cleanup cgroup eBPF device filter code
xattr: fix uninitialized out-param
Revert "cgroup: Add memory barriers to plug cgroup_rstat_updated() race window"
[Why]
We dropped the delay after changed the cursor functions locking the
entire pipe to locking just the CURSOR registers to fix page flip
stuttering - this introduced cursor stuttering instead, and an underflow
issue.
The cursor update can be delayed indefinitely if the cursor update
repeatedly happens right around VUPDATE.
The underflow issue can happen if we do a viewport update on a pipe
on the same frame where a cursor update happens around VUPDATE - the
old cursor registers are retained which can be in an invalid position.
This can cause a pipe hang and indefinite underflow.
[How]
The complex, ideal solution to the problem would be a software
triple buffering mechanism from the DM layer to program only one cursor
update per frame just before VUPDATE.
The simple workaround until we have that infrastructure in place is
this change - bring back the delay until VUPDATE before locking, but
with some corrections to the calculations.
This didn't work for all timings before because the calculation for
VUPDATE was wrong - it was using the offset from VSTARTUP instead and
didn't correctly handle the case where VUPDATE could be in the back
porch.
Add a new hardware sequencer function to use the existing helper to
calculate the real VUPDATE start and VUPDATE end - VUPDATE can last
multiple lines after all.
Change the udelay to incorporate the width of VUPDATE as well.
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
During the rework for removing the FPU issues, I found the following
warning:
[..] dml_common_defs.o: warning: objtool: dml_round()+0x9: FPU
instruction outside of kernel_fpu_{begin,end}()
This file has a single function that does not need to be in a specific
file. This commit drop dml_common_defs file, and move dml_round function
to dml_inline_defs.
CC: Christian König <christian.koenig@amd.com>
CC: Alexander Deucher <Alexander.Deucher@amd.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Tony Cheng <tony.cheng@amd.com>
CC: Harry Wentland <hwentlan@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
DP training sequence to set SCRAMBLING_DISABLE bit properly based on
training pattern - per DP Spec.
[How]
Update dpcd_pattern.v1_4.SCRAMBLING_DISABLE with 1 for TPS1, TPS2, TPS3,
but not for TPS4.
Signed-off-by: Vladimir Stempen <vladimir.stempen@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
If the mapping address is wrong then we have to release the reference to
it before returning -EINVAL.
Fixes: 088880ddc0 ("drm/etnaviv: implement softpin")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
The GC860 has one GPU device which has a 2d and 3d core. In this case
we want to expose perfmon information for both cores.
The driver has one array which contains all possible perfmon domains
with some meta data - doms_meta. Here we can see that for the GC860
two elements of that array are relevant:
doms_3d: is at index 0 in the doms_meta array with 8 perfmon domains
doms_2d: is at index 1 in the doms_meta array with 1 perfmon domain
The userspace driver wants to get a list of all perfmon domains and
their perfmon signals. This is done by iterating over all domains and
their signals. If the userspace driver wants to access the domain with
id 8 the kernel driver fails and returns invalid data from doms_3d with
and invalid offset.
This results in:
Unable to handle kernel paging request at virtual address 00000000
On such a device it is not possible to use the userspace driver at all.
The fix for this off-by-one error is quite simple.
Reported-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Paul Cercueil <paul@crapouillou.net>
Fixes: ed1dd899ba ("drm/etnaviv: rework perfmon query infrastructure")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
The opaque pointer passed to the IRQ handler is a pointer to the
drm_device, not a pointer to our ingenic_drm structure.
It still worked, because our ingenic_drm structure contains the
drm_device as its first field, so the pointer received had the same
value, but this was not semantically correct.
Cc: stable@vger.kernel.org # v5.3
Fixes: 90b86fcc47 ("DRM: Add KMS driver for the Ingenic JZ47xx SoCs")
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20200516215057.392609-5-paul@crapouillou.net
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Fix the following coccicheck warning:
drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:518:9-10: WARNING: return of 0/1
in function 'vmw_fence_obj_signaled' with return type bool
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Roland Scheidegger <sroland@vmware.com>
The variable ret is being initialized with a value that is never read
and it is being updated later with a new value. The initialization
is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Roland Scheidegger <sroland@vmware.com>
The parameter name should be interruptible instead of interuptable.
Signed-off-by: Guixiong Wei <guixiongwei@gmail.com>
Signed-off-by: Roland Scheidegger <sroland@vmware.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCXrz0qQAKCRDj7w1vZxhR
xSImAQDRwP5tNB3ZZmnJ2ABF2uqT+YTzS5oPW//bxCgnq128FQEA4UxFvgVOXAGI
HUsEGriyhoYgPMApmKHsFTTCvphlcQY=
=Igwt
-----END PGP SIGNATURE-----
Merge tag 'drm-misc-fixes-2020-05-14' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Just one meson patch this time to propagate an error code
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200514073538.wvdtv5s2mt4wdrdj@gilmour.lan
- Mark current submissions with a weak-dependency (Chris)
- Propagate errror from completed fences (Chris)
- Fixes on execlist to avoid GPU hang situation (Chris)
- Fixes couple deadlocks (Chris)
- Timeslice preemption fixes (Chris)
- Fix Display Port interrupt handling on Tiger Lake (Imre)
- Reduce debug noise around Frame Buffer Compression
+(Peter)
- Fix logic around IPC W/a for Coffee Lake and Kaby Lake
+(Sultan)
- Avoid dereferencing a dead context (Chris)
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEbSBwaO7dZQkcLOKj+mJfZA7rE8oFAl68wiMACgkQ+mJfZA7r
E8oIuwf+O5cOPgntlouifdbTtEmbZOFFOQhEggis8XnWK6wk5cspGsDuuzcVlp31
rc90KIjt/GjN/wxF3G30aU/SX876Fu4Y6bRpt6X6n1LheYkRwG3AfXOr3P3Le++e
W924tGCnjY7Nxip9MVj5pKy6nd1QKq/jtYT71aPapmSPBEzTIquDDOk73cwoWsJd
BbmF9KJ1BQbMjXjO5f6TOR62/Crea8qxUttB7Su0quldJHGkB9Lj2a6zmBsjDoIq
rdwBQg4seW3RVWPwSJD1/2oGofEQF46MssFk4moxoZjzRsHixI3qsBvRJvixtxpP
i38rmFkWYDymMv6JWtcO1KaKMRQCHA==
=BNra
-----END PGP SIGNATURE-----
Merge tag 'drm-intel-fixes-2020-05-13-1' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes
- Handle idling during i915_gem_evict_something busy loops (Chris)
- Mark current submissions with a weak-dependency (Chris)
- Propagate errror from completed fences (Chris)
- Fixes on execlist to avoid GPU hang situation (Chris)
- Fixes couple deadlocks (Chris)
- Timeslice preemption fixes (Chris)
- Fix Display Port interrupt handling on Tiger Lake (Imre)
- Reduce debug noise around Frame Buffer Compression
+(Peter)
- Fix logic around IPC W/a for Coffee Lake and Kaby Lake
+(Sultan)
- Avoid dereferencing a dead context (Chris)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200514040235.GA2164266@intel.com
This contains a pair of patches which fix SMMU support on Tegra124 and
Tegra210 for host1x and the Tegra DRM driver.
-----BEGIN PGP SIGNATURE-----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=DZJ0
-----END PGP SIGNATURE-----
Merge tag 'drm/tegra/for-5.7-fixes' of git://anongit.freedesktop.org/tegra/linux into drm-fixes
drm/tegra: Fixes for v5.7
This contains a pair of patches which fix SMMU support on Tegra124 and
Tegra210 for host1x and the Tegra DRM driver.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Thierry Reding <thierry.reding@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508101355.3031268-1-thierry.reding@gmail.com
- Fixes couple deadlocks (Chris)
- Timeslice preemption fixes (Chris)
- Fix Display Port interrupt handling on Tiger Lake (Imre)
- Reduce debug noise around Frame Buffer Compression (Peter)
- Fix logic around IPC W/a for Coffee Lake and Kaby Lake (Sultan)
- Avoid dereferencing a dead context (Chris)
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEbSBwaO7dZQkcLOKj+mJfZA7rE8oFAl607QgACgkQ+mJfZA7r
E8oP4gf+MxxjhkjPI+kmBDVE7f1kSnjYDdITWbmGPdzkaVEqTNwdmu2liYuy+Be0
qKtncD6/3Xs16JU905Ew7EbBODvDhWHkRJ2QH3MAPnu28qjFgDHl/tbbnYzWQsDJ
JNt0vYJ1jUpm+QrRy1W2woWO95fjsYzYDsVHhKZzVoiHmoEULH1XyFqJfYh4yoLZ
puKSj/LXGeVTRPEU9HL9Hhs2wpB5SI/pda7UgLMj0Cjc+3MkdDMPI9qKTOtlype8
yErtqGMYsMifSrKhaMXYPZCtGexScknUS5mq9WjGJITgd8LqACEeciP7twkO0ZMx
Del31B21K3Gjq9mdmv32Bur0LA++Dg==
=Byvp
-----END PGP SIGNATURE-----
Merge tag 'drm-intel-fixes-2020-05-07' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes
- Fixes on execlist to avoid GPU hang situation (Chris)
- Fixes couple deadlocks (Chris)
- Timeslice preemption fixes (Chris)
- Fix Display Port interrupt handling on Tiger Lake (Imre)
- Reduce debug noise around Frame Buffer Compression (Peter)
- Fix logic around IPC W/a for Coffee Lake and Kaby Lake (Sultan)
- Avoid dereferencing a dead context (Chris)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508052437.GA3212215@intel.com
i915_gem_evict_something() is charged with finding a slot within the GTT
that we may reuse. Since our goal is not to stall, we first look for a
slot that only overlaps idle vma. To this end, on the first pass we move
any active vma to the end of the search list. However, we only stopped
moving active vma after we see the first active vma twice. If during the
search, that first active vma completed, we would not notice and keep on
extending the search list.
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1746
Fixes: 2850748ef8 ("drm/i915: Pull i915_vma_pin under the vm->mutex")
Fixes: b1e3177bd1 ("drm/i915: Coordinate i915_active with its own mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200509115217.26853-1-chris@chris-wilson.co.uk
(cherry picked from commit 73e28cc40b)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
pm_resump api did not handle drm_mode_config_helper_resume error.
This change add handle to return drm_mode_config_helper_resume`s
error number. This code logic is aligned with api pm_suspend.
After this change, the code maybe a bit readable.
Signed-off-by: Bernard Zhao <bernard@vivo.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428131747.2099-1-bernard@vivo.com
[Why]
For MST case: when update_config is called to disable a stream,
this clears the settings for all the streams on that link.
We should only clear the settings for the stream that was disabled.
[How]
Clear the settings after the call to remove display is called.
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Leo (Hanghong) Ma <hanghong.ma@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
On my raven1 system (rev c6) with VBIOS 113-RAVEN-114 GFXOFF is
not stable (resulting in large block tiling noise in some applications).
Disabling GFXOFF via the quirk list fixes the problems for me.
Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
We recorded the dependencies for WAIT_FOR_SUBMIT in order that we could
correctly perform priority inheritance from the parallel branches to the
common trunk. However, for the purpose of timeslicing and reset
handling, the dependency is weak -- as we the pair of requests are
allowed to run in parallel and not in strict succession.
The real significance though is that this allows us to rearrange
groups of WAIT_FOR_SUBMIT linked requests along the single engine, and
so can resolve user level inter-batch scheduling dependencies from user
semaphores.
Fixes: c81471f5e9 ("drm/i915: Copy across scheduler behaviour flags across submit fences")
Testcase: igt/gem_exec_fence/submit
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507155109.8892-1-chris@chris-wilson.co.uk
(cherry picked from commit 6b6cd2ebd8)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
We need to preserve fatal errors from fences that are being terminated
as we hook them up.
Fixes: ef46884975 ("drm/i915: Propagate fence errors")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506162136.3325-1-chris@chris-wilson.co.uk
(cherry picked from commit 24fe5f2ab2)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
As i915 won't allocate extra PDP for current default PML4 table,
so for 3-level ppgtt guest, we would hit kernel pointer access
failure on extra PDP pointers. So this trys to bypass that now.
It won't impact real shadow PPGTT setup, so guest context still
works.
This is verified on 4.15 guest kernel with i915.enable_ppgtt=1
to force on old aliasing ppgtt behavior.
Fixes: 4f15665ccb ("drm/i915: Add ppgtt to GVT GEM context")
Reviewed-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200506095918.124913-1-zhenyuw@linux.intel.com
Init value of some display vregs rea inherited from host pregs. When
host display in different status, i.e. all monitors unpluged, different
display configurations, etc., GVT virtual display setup don't consistent
thus may lead to guest driver consider display goes malfunctional.
The added init vreg values are based on PRMs and fixed by calcuation
from current configuration (only PIPE_A) and the virtual EDID.
Fixes: 04d348ae3f ("drm/i915/gvt: vGPU display virtualization")
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200508060506.216250-1-colin.xu@intel.com
This patch adds a basic cursor check when an atomic test-only commit is
performed. The position and size of the cursor plane is checked.
This should fix user-space relying on atomic checks to assign buffers to
planes.
Signed-off-by: Simon Ser <contact@emersion.fr>
Reported-by: Roman Gilg <subdiff@gmail.com>
References: https://github.com/emersion/libliftoff/issues/46
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
[Why]
We're sending the drm vblank event a frame too early in the case where
the pageflip happens close to VUPDATE and ends up blocking the signal.
The implementation in DM was previously correct *before* we started
sending vblank events from VSTARTUP unconditionally to handle cases
where HUBP was off, OTG was ON and userspace was still requesting some
DRM planes enabled. As part of that patch series we dropped VUPDATE
since it was deemed close enough to VSTARTUP, but there's a key
difference betweeen VSTARTUP and VUPDATE - the VUPDATE signal can be
blocked if we're holding the pipe lock.
There was a fix recently to revert the unconditional behavior for the
DCN VSTARTUP vblank event since it was sending the pageflip event on
the wrong frame - once again, due to blocking VUPDATE and having the
address start scanning out two frames later.
The problem with this fix is it didn't update the logic that calls
drm_crtc_handle_vblank(), so the timestamps are totally bogus now.
[How]
Essentially reverts most of the original VSTARTUP series but retains
the behavior to send back events when active planes == 0.
Some refactoring/cleanup was done to not have duplicated code in both
the handlers.
Fixes: 16f17eda8b ("drm/amd/display: Send vblank and user events at vsartup for DCN")
Fixes: 3a2ce8d66a ("drm/amd/display: Disable VUpdate interrupt for DCN hardware")
Fixes: 2b5aed9ac3 ("drm/amd/display: Fix pageflip event race condition for DCN.")
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-and-Tested-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org # 5.6.x
Same as gfx9. This allows us to kill the waves for hung
shaders.
Acked-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
BACO is needed to support hibernate on Navi1X.
Signed-off-by: Evan Quan <evan.quan@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Releasing the AMDGPU BO ref directly leads to problems when BOs were
exported as DMA bufs. Releasing the GEM reference makes sure that the
AMDGPU/TTM BO is not freed too early.
Also take a GEM reference when importing BOs from DMABufs to keep
references to imported BOs balances properly.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Tested-by: Alex Sierra <alex.sierra@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Sierra <alex.sierra@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
We set the fb smem pointer to the offset into the BAR, so keep
the fbdev bo in vram.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=207581
Fixes: 6c8d74caa2 ("drm/amdgpu: Enable scatter gather display support")
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Since gfxoff should be disabled first before trying to access those
GC registers.
Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
