In order to avoid confusing the HW, we must never submit an empty ring
during lite-restore, that is we should always advance the RING_TAIL
before submitting to stay ahead of the RING_HEAD.
Normally this is prevented by keeping a couple of spare NOPs in the
request->wa_tail so that on resubmission we can advance the tail. This
relies on the request only being resubmitted once, which is the normal
condition as it is seen once for ELSP[1] and then later in ELSP[0]. On
preemption, the requests are unwound and the tail reset back to the
normal end point (as we know the request is incomplete and therefore its
RING_HEAD is even earlier).
However, if this w/a should fail we would try and resubmit the request
with the RING_TAIL already set to the location of this request's wa_tail
potentially causing a GPU hang. We can spot when we do try and
incorrectly resubmit without advancing the RING_TAIL and spare any
embarrassment by forcing the context restore.
In the case of preempt-to-busy, we leave the requests running on the HW
while we unwind. As the ring is still live, we cannot rewind our
rq->tail without forcing a reload so leave it set to rq->wa_tail and
only force a reload if we resubmit after a lite-restore. (Normally, the
forced reload will be a part of the preemption event.)
Fixes: 22b7a426bb ("drm/i915/execlists: Preempt-to-busy")
Closes: https://gitlab.freedesktop.org/drm/intel/issues/673
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: stable@kernel.vger.org
Link: https://patchwork.freedesktop.org/patch/msgid/20191209023215.3519970-1-chris@chris-wilson.co.uk
We now only use 1 client without any plan to add more. The client is
also only holding information about the WQ and the process desc, so we
can just move those in the intel_guc structure and always use stage_id
0.
v2: fix comment (John)
v3: fix the comment for real, fix kerneldoc
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191205220243.27403-4-daniele.ceraolospurio@intel.com
Instead of relying on the workqueue, the upcoming reworked GuC
submission flow will offer the host driver indipendent control over
the execution status of each context submitted to GuC. As part of this,
the doorbell usage model has been reworked, with each doorbell being
paired to a single lrc and a doorbell ring representing new work
available for that specific context. This mechanism, however, limits
the number of contexts that can be registered with GuC to the number of
doorbells, which is an undesired limitation. To avoid this limitation,
we requested the GuC team to also provide a H2G that will allow the host
to notify the GuC of work available for a specified lrc, so we can use
that mechanism instead of relying on the doorbells. We can therefore drop
the doorbell code we currently have, also given the fact that in the
unlikely case we'd want to switch back to using doorbells we'd have to
heavily rework it.
The workqueue will still have a use in the new interface to pass special
commands, so that code has been retained for now.
With the doorbells gone and the GuC client becoming even simpler, the
existing GuC selftests don't give us any meaningful coverage so we can
remove them as well. Some selftests might come with the new code, but
they will look different from what we have now so if doesn't seem worth
it to keep the file around in the meantime.
v2: fix comments and commit message (John)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191205220243.27403-3-daniele.ceraolospurio@intel.com
We already have a couple of use-cases in the code and another one will
come in one of the later patches in the series.
v2: use the new function for the CT object as well
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> #v1
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191205220243.27403-2-daniele.ceraolospurio@intel.com
Remove unused enums and ctx_save_restore_disabled() function, leftover
from the legacy preemption removal.
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191205220243.27403-1-daniele.ceraolospurio@intel.com
intel_hdcp_transcoder_config() is clobbering some globally visible
state in .compute_config(). That is a big no no as .compute_config()
is supposed to have no visible side effects when either the commit
fails or it's just a TEST_ONLY commit.
Inline this stuff into intel_hdcp_enable() so that the state only
gets modified when we actually commit the state to the hardware.
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Fixes: 39e2df090c ("drm/i915/hdcp: update current transcoder into intel_hdcp")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191204180549.1267-2-ville.syrjala@linux.intel.com
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
The code assumes we can omit the cfb allocation once fbc
has been enabled once. That's nonsense. Let's try to
reallocate it if we need to.
The code is still a mess, but maybe this is enough to get
fbc going in some cases where it initially underallocates
the cfb and there's no full modeset to fix it up.
Cc: Daniel Drake <drake@endlessm.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jian-Hong Pan <jian-hong@endlessm.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-15-ville.syrjala@linux.intel.com
Tested-by: Daniel Drake <drake@endlessm.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Now that we have the glk+ w/a for back to back fbc disable + plane
update in place we can once more enable fbc on glk+ by default.
Cc: Daniel Drake <drake@endlessm.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jian-Hong Pan <jian-hong@endlessm.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-14-ville.syrjala@linux.intel.com
Tested-by: Daniel Drake <drake@endlessm.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
On glk+ the hardware gets confused if we disable FBC while
it's recompressing and we perform a plane update during the
same frame. The result is that top of the screen gets corrupted.
We can avoid that by giving the hardware enough time to finish
the FBC disable before we touch the plane registers. Ie. we need
an extra vblank wait after FBC disable.
v2: Don't do the vblank wait if we never activated FBC in hw
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191128150338.12490-1-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
The hardware automagically nukes the cfb on flip. We can use
that whenever the plane/crtc configuration doesn't change too
much. Let's hook that up.
We'll need this for glk+ since we need to introduce an extra
vblank wait after FBC disable. As we're currently disabling
FBC around all plane updates we'd slow them down by an extra
frame. Not a great user experience when your fps is always
capped at vrefres/2. With flip nuke we don't need the extra
vblank wait.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-12-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
i965gm no longer needs the fence for scanout so we should be
do what we do for ctg+ and only configure a fence for FBC
when we have one.
In theory this should do nothing atm on account of
intel_fbc_can_activate() requiring the fence, but since
we do this for g4x+ let's do it for i965gm as well. We
may want to relax the requirements at some point and allow
FBC without a fence.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-9-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Precompute the override cfb stride value so that we can check
it when determining if flip nuke can be used or not.
The hardware has 13 bits for this, so we can shrink the storage
to u16 while at it.
v2: Don't explode when crtc_state->enable_fbc lies to us
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-6-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
We don't want to use the FBC hardware render tracking so let's not
enable it. To use the hw tracking properly we'd anyway need to
integrate this into the command submissing path as the register is
context saved, and if rendering happens via the ppgtt we'd have
to configure it with the ppgtt address instead of the ggtt address.
Easier to use software tracking instead.
Note that on pre-ilk we can't actually disable render tracking.
However we can't rely on it because it requires that DSPSURF to
match the render target address, and since we play tricks
with DSPSURF that may not be the case. Hence we shall rely on
software render tracking on all platforms.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-5-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
We're missing a workaround in the fbc code for all glk+ platforms
which can cause corruption around the top of the screen. So
enabling fbc by default is a bad idea. I'm not keen to backport
the w/a so let's start by disabling fbc by default on all glk+.
We'll lift the restriction once the w/a is in place.
Cc: stable@vger.kernel.org
Cc: Daniel Drake <drake@endlessm.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jian-Hong Pan <jian-hong@endlessm.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-2-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Gen12 supports saving/restoring render counters per context. Apply OAR
configuration only for the context that is passed in to perf.
v2:
- Fix OACTXCONTROL value to only stop/resume counters.
- Remove gen12_update_reg_state_unlocked as power state is already
applied by the caller.
v3: (Lionel)
- Move register initialization into the array
- Assume a valid oa_config in enable_metric_set
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Fixes: 00a7f0d715 ("drm/i915/tgl: Add perf support on TGL")
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191206194339.31356-2-umesh.nerlige.ramappa@intel.com
SAMPLE_OA_REPORT enables sampling of OA reports from the OA buffer.
Since reports from OA buffer had system wide visibility, collecting
samples from the OA buffer was a privileged operation on previous
platforms. Prior to TGL, it was also necessary to sample the OA buffer
to normalize reports from MI REPORT PERF COUNT.
TGL has a dedicated OAR unit to sample perf reports for a specific
render context. This removes the necessity to sample OA buffer.
- If not sampling the OA buffer, allow non-privileged access. An earlier
patch allows the non-privilege access:
https://patchwork.freedesktop.org/patch/337716/?series=68582&rev=1
- Clear up the path for non-privileged access in this patch
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Fixes: 00a7f0d715 ("drm/i915/tgl: Add perf support on TGL")
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191206194339.31356-1-umesh.nerlige.ramappa@intel.com
Since we didn't check and insist that args.pad must be zero for MMAP_GTT
historically, we cannot insert a check now as old userspace may be
feeding in garbage. As such the lack of check is enshrined into the ABI,
so add a comment to remind us we cannot add the check later.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191207222644.2830129-1-chris@chris-wilson.co.uk
Pull networking fixes from David Miller:
1) More jumbo frame fixes in r8169, from Heiner Kallweit.
2) Fix bpf build in minimal configuration, from Alexei Starovoitov.
3) Use after free in slcan driver, from Jouni Hogander.
4) Flower classifier port ranges don't work properly in the HW offload
case, from Yoshiki Komachi.
5) Use after free in hns3_nic_maybe_stop_tx(), from Yunsheng Lin.
6) Out of bounds access in mqprio_dump(), from Vladyslav Tarasiuk.
7) Fix flow dissection in dsa TX path, from Alexander Lobakin.
8) Stale syncookie timestampe fixes from Guillaume Nault.
[ Did an evil merge to silence a warning introduced by this pull - Linus ]
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
r8169: fix rtl_hw_jumbo_disable for RTL8168evl
net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add()
r8169: add missing RX enabling for WoL on RTL8125
vhost/vsock: accept only packets with the right dst_cid
net: phy: dp83867: fix hfs boot in rgmii mode
net: ethernet: ti: cpsw: fix extra rx interrupt
inet: protect against too small mtu values.
gre: refetch erspan header from skb->data after pskb_may_pull()
pppoe: remove redundant BUG_ON() check in pppoe_pernet
tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE()
tcp: tighten acceptance of ACKs not matching a child socket
tcp: fix rejected syncookies due to stale timestamps
lpc_eth: kernel BUG on remove
tcp: md5: fix potential overestimation of TCP option space
net: sched: allow indirect blocks to bind to clsact in TC
net: core: rename indirect block ingress cb function
net-sysfs: Call dev_hold always in netdev_queue_add_kobject
net: dsa: fix flow dissection on Tx path
net/tls: Fix return values to avoid ENOTSUPP
net: avoid an indirect call in ____sys_recvmsg()
...
11 patches, all in drivers (no core changes) that are either minor
cleanups or small fixes. They were late arriving, but still safe for
-rc1.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull more SCSI updates from James Bottomley:
"Eleven patches, all in drivers (no core changes) that are either minor
cleanups or small fixes.
They were late arriving, but still safe for -rc1"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: MAINTAINERS: Add the linux-scsi mailing list to the ISCSI entry
scsi: megaraid_sas: Make poll_aen_lock static
scsi: sd_zbc: Improve report zones error printout
scsi: qla2xxx: Fix qla2x00_request_irqs() for MSI
scsi: qla2xxx: unregister ports after GPN_FT failure
scsi: qla2xxx: fix rports not being mark as lost in sync fabric scan
scsi: pm80xx: Remove unused include of linux/version.h
scsi: pm80xx: fix logic to break out of loop when register value is 2 or 3
scsi: scsi_transport_sas: Fix memory leak when removing devices
scsi: lpfc: size cpu map by last cpu id set
scsi: ibmvscsi_tgt: Remove unneeded variable rc
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Merge tag '5.5-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Nine cifs/smb3 fixes:
- one fix for stable (oops during oplock break)
- two timestamp fixes including important one for updating mtime at
close to avoid stale metadata caching issue on dirty files (also
improves perf by using SMB2_CLOSE_FLAG_POSTQUERY_ATTRIB over the
wire)
- two fixes for "modefromsid" mount option for file create (now
allows mode bits to be set more atomically and accurately on create
by adding "sd_context" on create when modefromsid specified on
mount)
- two fixes for multichannel found in testing this week against
different servers
- two small cleanup patches"
* tag '5.5-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
smb3: improve check for when we send the security descriptor context on create
smb3: fix mode passed in on create for modetosid mount option
cifs: fix possible uninitialized access and race on iface_list
cifs: Fix lookup of SMB connections on multichannel
smb3: query attributes on file close
smb3: remove unused flag passed into close functions
cifs: remove redundant assignment to pointer pneg_ctxt
fs: cifs: Fix atime update check vs mtime
CIFS: Fix NULL-pointer dereference in smb2_push_mandatory_locks
Pull misc vfs cleanups from Al Viro:
"No common topic, just three cleanups".
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
make __d_alloc() static
fs/namespace: add __user to open_tree and move_mount syscalls
fs/fnctl: fix missing __user in fcntl_rw_hint()
"Have you tried switching it off and on again?"
Set the size of the mm to 0 to disable all PD cachelines, before
enabling the whole mm again. Let's see if that tricks the TLB into
reloading.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191208143648.2986669-1-chris@chris-wilson.co.uk
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Merge tag 'ntb-5.5' of git://github.com/jonmason/ntb
Pull NTB update from Jon Mason:
"Just a simple patch to add a new Hygon Device ID to the AMD NTB device
driver"
* tag 'ntb-5.5' of git://github.com/jonmason/ntb:
NTB: Add Hygon Device ID
Pull more input updates from Dmitry Torokhov:
- fixups for Synaptics RMI4 driver
- a quirk for Goodinx touchscreen on Teclast tablet
- a new keycode definition for activating privacy screen feature found
on a few "enterprise" laptops
- updates to snvs_pwrkey driver
- polling uinput device for writing (which is always allowed) now works
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: synaptics-rmi4 - don't increment rmiaddr for SMBus transfers
Input: synaptics-rmi4 - re-enable IRQs in f34v7_do_reflash
Input: goodix - add upside-down quirk for Teclast X89 tablet
Input: add privacy screen toggle keycode
Input: uinput - fix returning EPOLLOUT from uinput_poll
Input: snvs_pwrkey - remove gratuitous NULL initializers
Input: snvs_pwrkey - send key events for i.MX6 S, DL and Q
- Fix a UAF when reporting writeback errors
- Fix a race condition when handling page uptodate on a blocksize <
pagesize file that is also fragmented
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Merge tag 'iomap-5.5-merge-14' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fixes from Darrick Wong:
"Fix a race condition and a use-after-free error:
- Fix a UAF when reporting writeback errors
- Fix a race condition when handling page uptodate on fragmented file
with blocksize < pagesize"
* tag 'iomap-5.5-merge-14' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: stop using ioend after it's been freed in iomap_finish_ioend()
iomap: fix sub-page uptodate handling
- Fix a crash in the log setup code when log mounting fails
- Fix a hang when allocating space on the realtime device
- Fix a block leak when freeing space on the realtime device
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Merge tag 'xfs-5.5-merge-17' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"Fix a couple of resource management errors and a hang:
- fix a crash in the log setup code when log mounting fails
- fix a hang when allocating space on the realtime device
- fix a block leak when freeing space on the realtime device"
* tag 'xfs-5.5-merge-17' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix mount failure crash on invalid iclog memory access
xfs: don't check for AG deadlock for realtime files in bunmapi
xfs: fix realtime file data space leak
Orangefs has no open, and orangefs checks file permissions
on each file access. Posix requires that file permissions
be checked on open and nowhere else. Orangefs-through-the-kernel
needs to seem posix compliant.
The VFS opens files, even if the filesystem provides no
method. We can see if a file was successfully opened for
read and or for write by looking at file->f_mode.
When writes are flowing from the page cache, file is no
longer available. We can trust the VFS to have checked
file->f_mode before writing to the page cache.
The mode of a file might change between when it is opened
and IO commences, or it might be created with an arbitrary mode.
We'll make sure we don't hit EACCES during the IO stage by
using UID 0.
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Merge tag 'for-linus-5.5-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs update from Mike Marshall:
"orangefs: posix open permission checking...
Orangefs has no open, and orangefs checks file permissions on each
file access. Posix requires that file permissions be checked on open
and nowhere else. Orangefs-through-the-kernel needs to seem posix
compliant.
The VFS opens files, even if the filesystem provides no method. We can
see if a file was successfully opened for read and or for write by
looking at file->f_mode.
When writes are flowing from the page cache, file is no longer
available. We can trust the VFS to have checked file->f_mode before
writing to the page cache.
The mode of a file might change between when it is opened and IO
commences, or it might be created with an arbitrary mode.
We'll make sure we don't hit EACCES during the IO stage by using
UID 0"
[ This is "posixish", but not a great solution in the long run, since a
proper secure network server shouldn't really trust the client like this.
But proper and secure POSIX behavior requires an open method and a
resulting cookie for IO of some kind, or similar. - Linus ]
* tag 'for-linus-5.5-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: posix open permission checking...
Possibly most interesting is Trond's fixes for some callback races that
were due to my incomplete understanding of rpc client shutdown.
Unfortunately at the last minute I've started noticing a new
intermittent failure to send callbacks. As the logic seems basically
correct, I'm leaving Trond's patches in for now, and hope to find a fix
in the next week so I don't have to revert those patches.
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Merge tag 'nfsd-5.5' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"This is a relatively quiet cycle for nfsd, mainly various bugfixes.
Possibly most interesting is Trond's fixes for some callback races
that were due to my incomplete understanding of rpc client shutdown.
Unfortunately at the last minute I've started noticing a new
intermittent failure to send callbacks. As the logic seems basically
correct, I'm leaving Trond's patches in for now, and hope to find a
fix in the next week so I don't have to revert those patches"
* tag 'nfsd-5.5' of git://linux-nfs.org/~bfields/linux: (24 commits)
nfsd: depend on CRYPTO_MD5 for legacy client tracking
NFSD fixing possible null pointer derefering in copy offload
nfsd: check for EBUSY from vfs_rmdir/vfs_unink.
nfsd: Ensure CLONE persists data and metadata changes to the target file
SUNRPC: Fix backchannel latency metrics
nfsd: restore NFSv3 ACL support
nfsd: v4 support requires CRYPTO_SHA256
nfsd: Fix cld_net->cn_tfm initialization
lockd: remove __KERNEL__ ifdefs
sunrpc: remove __KERNEL__ ifdefs
race in exportfs_decode_fh()
nfsd: Drop LIST_HEAD where the variable it declares is never used.
nfsd: document callback_wq serialization of callback code
nfsd: mark cb path down on unknown errors
nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback()
nfsd: minor 4.1 callback cleanup
SUNRPC: Fix svcauth_gss_proxy_init()
SUNRPC: Trace gssproxy upcall results
sunrpc: fix crash when cache_head become valid before update
nfsd: remove private bin2hex implementation
...
Highlights include:
Features:
- NFSv4.2 now supports cross device offloaded copy (i.e. offloaded copy
of a file from one source server to a different target server).
- New RDMA tracepoints for debugging congestion control and Local Invalidate
WRs.
Bugfixes and cleanups
- Drop the NFSv4.1 session slot if nfs4_delegreturn_prepare waits for
layoutreturn
- Handle bad/dead sessions correctly in nfs41_sequence_process()
- Various bugfixes to the delegation return operation.
- Various bugfixes pertaining to delegations that have been revoked.
- Cleanups to the NFS timespec code to avoid unnecessary conversions
between timespec and timespec64.
- Fix unstable RDMA connections after a reconnect
- Close race between waking an RDMA sender and posting a receive
- Wake pending RDMA tasks if connection fails
- Fix MR list corruption, and clean up MR usage
- Fix another RPCSEC_GSS issue with MIC buffer space
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Merge tag 'nfs-for-5.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- NFSv4.2 now supports cross device offloaded copy (i.e. offloaded
copy of a file from one source server to a different target
server).
- New RDMA tracepoints for debugging congestion control and Local
Invalidate WRs.
Bugfixes and cleanups
- Drop the NFSv4.1 session slot if nfs4_delegreturn_prepare waits for
layoutreturn
- Handle bad/dead sessions correctly in nfs41_sequence_process()
- Various bugfixes to the delegation return operation.
- Various bugfixes pertaining to delegations that have been revoked.
- Cleanups to the NFS timespec code to avoid unnecessary conversions
between timespec and timespec64.
- Fix unstable RDMA connections after a reconnect
- Close race between waking an RDMA sender and posting a receive
- Wake pending RDMA tasks if connection fails
- Fix MR list corruption, and clean up MR usage
- Fix another RPCSEC_GSS issue with MIC buffer space"
* tag 'nfs-for-5.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
SUNRPC: Capture completion of all RPC tasks
SUNRPC: Fix another issue with MIC buffer space
NFS4: Trace lock reclaims
NFS4: Trace state recovery operation
NFSv4.2 fix memory leak in nfs42_ssc_open
NFSv4.2 fix kfree in __nfs42_copy_file_range
NFS: remove duplicated include from nfs4file.c
NFSv4: Make _nfs42_proc_copy_notify() static
NFS: Fallocate should use the nfs4_fattr_bitmap
NFS: Return -ETXTBSY when attempting to write to a swapfile
fs: nfs: sysfs: Remove NULL check before kfree
NFS: remove unneeded semicolon
NFSv4: add declaration of current_stateid
NFSv4.x: Drop the slot if nfs4_delegreturn_prepare waits for layoutreturn
NFSv4.x: Handle bad/dead sessions correctly in nfs41_sequence_process()
nfsv4: Move NFSPROC4_CLNT_COPY_NOTIFY to end of list
SUNRPC: Avoid RPC delays when exiting suspend
NFS: Add a tracepoint in nfs_fh_to_dentry()
NFSv4: Don't retry the GETATTR on old stateid in nfs4_delegreturn_done()
NFSv4: Handle NFS4ERR_OLD_STATEID in delegreturn
...
Our asserts allow for the PDEs to be allocated concurrently, but we did
not account for the aliasing-ppgtt to be preallocated on top.
Testcase: igt/gem_ppgtt #bsw
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191207221453.2802627-1-chris@chris-wilson.co.uk
We had cases in the previous patch where we were sending the security
descriptor context on SMB3 open (file create) in cases when we hadn't
mounted with with "modefromsid" mount option.
Add check for that mount flag before calling ad_sd_context in
open init.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
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Merge tag 'for-linus-5.5b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull more xen updates from Juergen Gross:
- a patch to fix a build warning
- a cleanup of no longer needed code in the Xen event handling
- a small series for the Xen grant driver avoiding high order
allocations and replacing an insane global limit by a per-call one
- a small series fixing Xen frontend/backend module referencing
* tag 'for-linus-5.5b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen-blkback: allow module to be cleanly unloaded
xen/xenbus: reference count registered modules
xen/gntdev: switch from kcalloc() to kvcalloc()
xen/gntdev: replace global limit of mapped pages by limit per call
xen/gntdev: remove redundant non-zero check on ret
xen/events: remove event handling recursion detection
Merge misc Kconfig updates from Andrew Morton:
"A number of changes to Kconfig files under lib/ from Changbin Du and
Krzysztof Kozlowski"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
lib/: fix Kconfig indentation
kernel-hacking: move DEBUG_FS to 'Generic Kernel Debugging Instruments'
kernel-hacking: move DEBUG_BUGVERBOSE to 'printk and dmesg options'
kernel-hacking: create a submenu for scheduler debugging options
kernel-hacking: move SCHED_STACK_END_CHECK after DEBUG_STACK_USAGE
kernel-hacking: move Oops into 'Lockups and Hangs'
kernel-hacking: move kernel testing and coverage options to same submenu
kernel-hacking: group kernel data structures debugging together
kernel-hacking: create submenu for arch special debugging options
kernel-hacking: group sysrq/kgdb/ubsan into 'Generic Kernel Debugging Instruments'
In referenced fix we removed the RTL8168e-specific jumbo config for
RTL8168evl in rtl_hw_jumbo_enable(). We have to do the same in
rtl_hw_jumbo_disable().
v2: fix referenced commit id
Fixes: 14012c9f3b ("r8169: fix jumbo configuration for RTL8168evl")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
pipe_wait() may be simple, but since it relies on the pipe lock, it
means that we have to do the wakeup while holding the lock. That's
unfortunate, because the very first thing the waked entity will want to
do is to get the pipe lock for itself.
So get rid of the pipe_wait() usage by simply releasing the pipe lock,
doing the wakeup (if required) and then using wait_event_interruptible()
to wait on the right condition instead.
wait_event_interruptible() handles races on its own by comparing the
wakeup condition before and after adding itself to the wait queue, so
you can use an optimistic unlocked condition for it.
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This code is ancient, and goes back to when we only had a single page
for the pipe buffers. The exact history is hidden in the mists of time
(ie "before git", and in fact predates the BK repository too).
At that long-ago point in time, it actually helped to try to merge big
back-and-forth pipe reads and writes, and not limit pipe reads to the
single pipe buffer in length just because that was all we had at a time.
However, since then we've expanded the pipe buffers to multiple pages,
and this logic really doesn't seem to make sense. And a lot of it is
somewhat questionable (ie "hmm, the user asked for a non-blocking read,
but we see that there's a writer pending, so let's wait anyway to get
the extra data that the writer will have").
But more importantly, it makes the "go to sleep" logic much less
obvious, and considering the wakeup issues we've had, I want to make for
less of those kinds of things.
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the read side version of the previous commit: it simplifies the
logic to only wake up waiting writers when necessary, and makes sure to
use a synchronous wakeup. This time not so much for GNU make jobserver
reasons (that pipe never fills up), but simply to get the writer going
quickly again.
A bit less verbose commentary this time, if only because I assume that
the write side commentary isn't going to be ignored if you touch this
code.
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The pipe rework ends up having been extra painful, partly becaused of
actual bugs with ordering and caching of the pipe state, but also
because of subtle performance issues.
In particular, the pipe rework caused the kernel build to inexplicably
slow down.
The reason turns out to be that the GNU make jobserver (which limits the
parallelism of the build) uses a pipe to implement a "token" system: a
parallel submake will read a character from the pipe to get the job
token before starting a new job, and will write a character back to the
pipe when it is done. The overall job limit is thus easily controlled
by just writing the appropriate number of initial token characters into
the pipe.
But to work well, that really means that the old behavior of write
wakeups being synchronous (WF_SYNC) is very important - when the pipe
writer wakes up a reader, we want the reader to actually get scheduled
immediately. Otherwise you lose the parallelism of the build.
The pipe rework lost that synchronous wakeup on write, and we had
clearly all forgotten the reasons and rules for it.
This rewrites the pipe write wakeup logic to do the required Wsync
wakeups, but also clarifies the logic and avoids extraneous wakeups.
It also ends up addign a number of comments about what oit does and why,
so that we hopefully don't end up forgetting about this next time we
change this code.
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
