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Pull ring buffer fixes from Steven Rostedt:
- Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU
hotplug"
A crash that happened on cpu hotplug was actually caused by the
incorrect ref counting that was fixed by commit 2cf9733891a4
("ring-buffer: Fix refcount setting of boot mapped buffers"). The
removal of calling cpu hotplug callbacks on memory mapped buffers was
not an issue even though the tests at the time pointed toward it. But
in fact, there's a check in that code that tests to see if the
buffers are already allocated or not, and will not allocate them
again if they are. Not calling the cpu hotplug callbacks ended up not
initializing the non boot CPU buffers.
Simply remove that change.
- Clear all CPU buffers when starting tracing in a boot mapped buffer
To properly process events from a previous boot, the address space
needs to be accounted for due to KASLR and the events in the buffer
are updated accordingly when read. This also requires that when the
buffer has tracing enabled again in the current boot that the buffers
are reset so that events from the previous boot do not interact with
the events of the current boot and cause confusing due to not having
the proper meta data.
It was found that if a CPU is taken offline, that its per CPU buffer
is not reset when tracing starts. This allows for events to be from
both the previous boot and the current boot to be in the buffer at
the same time. Clear all CPU buffers when tracing is started in a
boot mapped buffer.
* tag 'trace-ringbuffer-v6.12-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/ring-buffer: Clear all memory mapped CPU ring buffers on first recording
Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU hotplug"
Pull RISC-V fix from Palmer Dabbelt:
- A fix for the CPU perf driver that avoids leaking CPU ID references
on systems without snapshot support.
* tag 'riscv-for-linus-6.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
drivers: perf: Fix wrong put_cpu() placement
The events of a memory mapped ring buffer from the previous boot should
not be mixed in with events from the current boot. There's meta data that
is used to handle KASLR so that function names can be shown properly.
Also, since the timestamps of the previous boot have no meaning to the
timestamps of the current boot, having them intermingled in a buffer can
also cause confusion because there could possibly be events in the future.
When a trace is activated the meta data is reset so that the pointers of
are now processed for the new address space. The trace buffers are reset
when tracing starts for the first time. The problem here is that the reset
only happens on online CPUs. If a CPU is offline, it does not get reset.
To demonstrate the issue, a previous boot had tracing enabled in the boot
mapped ring buffer on reboot. On the following boot, tracing has not been
started yet so the function trace from the previous boot is still visible.
# trace-cmd show -B boot_mapped -c 3 | tail
<idle>-0 [003] d.h2. 156.462395: __rcu_read_lock <-cpu_emergency_disable_virtualization
<idle>-0 [003] d.h2. 156.462396: vmx_emergency_disable_virtualization_cpu <-cpu_emergency_disable_virtualization
<idle>-0 [003] d.h2. 156.462396: __rcu_read_unlock <-__sysvec_reboot
<idle>-0 [003] d.h2. 156.462397: stop_this_cpu <-__sysvec_reboot
<idle>-0 [003] d.h2. 156.462397: set_cpu_online <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462397: disable_local_APIC <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462398: clear_local_APIC <-disable_local_APIC
<idle>-0 [003] d.h2. 156.462574: mcheck_cpu_clear <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462575: mce_intel_feature_clear <-stop_this_cpu
<idle>-0 [003] d.h2. 156.462575: lmce_supported <-mce_intel_feature_clear
Now, if CPU 3 is taken offline, and tracing is started on the memory
mapped ring buffer, the events from the previous boot in the CPU 3 ring
buffer is not reset. Now those events are using the meta data from the
current boot and produces just hex values.
# echo 0 > /sys/devices/system/cpu/cpu3/online
# trace-cmd start -B boot_mapped -p function
# trace-cmd show -B boot_mapped -c 3 | tail
<idle>-0 [003] d.h2. 156.462395: 0xffffffff9a1e3194 <-0xffffffff9a0f655e
<idle>-0 [003] d.h2. 156.462396: 0xffffffff9a0a1d24 <-0xffffffff9a0f656f
<idle>-0 [003] d.h2. 156.462396: 0xffffffff9a1e6bc4 <-0xffffffff9a0f7323
<idle>-0 [003] d.h2. 156.462397: 0xffffffff9a0d12b4 <-0xffffffff9a0f732a
<idle>-0 [003] d.h2. 156.462397: 0xffffffff9a1458d4 <-0xffffffff9a0d12e2
<idle>-0 [003] d.h2. 156.462397: 0xffffffff9a0faed4 <-0xffffffff9a0d12e7
<idle>-0 [003] d.h2. 156.462398: 0xffffffff9a0faaf4 <-0xffffffff9a0faef2
<idle>-0 [003] d.h2. 156.462574: 0xffffffff9a0e3444 <-0xffffffff9a0d12ef
<idle>-0 [003] d.h2. 156.462575: 0xffffffff9a0e4964 <-0xffffffff9a0d12ef
<idle>-0 [003] d.h2. 156.462575: 0xffffffff9a0e3fb0 <-0xffffffff9a0e496f
Reset all CPUs when starting a boot mapped ring buffer for the first time,
and not just the online CPUs.
Fixes: 7a1d1e4b9639f ("tracing/ring-buffer: Add last_boot_info file to boot instance")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull drm fixes from Dave Airlie:
"Final week of fixes, lots of small amdgpu fixes, some i915 and xe
fixes, the nouveau changes fix a recent regression and some laptop
panel black screens, then a couple of other misc ones.
It's probably a little busier than I'd like, but each fix seems fine.
amdgpu:
- PSR fix
- Panel replay fixes
- DML fix
- vblank power fix
- Fix video caps
- SMU 14.0 fix
- GPUVM fix
- MES 12 fix
- APU carve out fix
- DC vbios fix
- NBIO fix
i915:
- Don't load GSC on ARL-H and ARL-U if too old FW
- Avoid potential OOPS in enabling/disabling TV output
xe:
- Fix unlock on exec ioctl error path
- Fix hibernation on LNL due to ggtt getting lost
- Fix missing runtime PM in OA release
bridge:
- tc358768: Fix DSI command tx
nouveau:
- Fix GSP AUX error handling
- dp: Handle retires for AUX CH transfers with GSP
- fw: Sync DMA after setup
panthor:
- Fix partial BO mappings to GPU
rockchip:
- vop: Avoid null-ptr deref in plane-state check
vmwgfx:
- Avoid null-ptr deref in surface creation"
* tag 'drm-fixes-2024-11-16' of https://gitlab.freedesktop.org/drm/kernel: (27 commits)
drm/bridge: tc358768: Fix DSI command tx
drm/vmwgfx: avoid null_ptr_deref in vmw_framebuffer_surface_create_handle
nouveau/dp: handle retries for AUX CH transfers with GSP.
nouveau: handle EBUSY and EAGAIN for GSP aux errors.
nouveau: fw: sync dma after setup is called.
drm/xe/oa: Fix "Missing outer runtime PM protection" warning
drm/xe: handle flat ccs during hibernation on igpu
drm/xe: improve hibernation on igpu
drm/xe: Restore system memory GGTT mappings
drm/xe: Ensure all locks released in exec IOCTL
drm/panthor: Fix handling of partial GPU mapping of BOs
drm/amd: Fix initialization mistake for NBIO 7.7.0
Revert "drm/amd/display: parse umc_info or vram_info based on ASIC"
drm/amd/display: Fix failure to read vram info due to static BP_RESULT
drm/amdgpu: enable GTT fallback handling for dGPUs only
drm/i915: Grab intel_display from the encoder to avoid potential oopsies
drm/i915/gsc: ARL-H and ARL-U need a newer GSC FW.
drm/amdgpu/mes12: correct kiq unmap latency
drm/amdgpu: fix check in gmc_v9_0_get_vm_pte()
drm/amd/pm: print pp_dpm_mclk in ascending order on SMU v14.0.0
...
Unfortunately, the wrong patch version was merged which places the
put_cpu() after enabling a static key, which is not safe as pointed by
Will [1], so move put_cpu() before to avoid this.
Fixes: 2840dadf0dde ("drivers: perf: Fix smp_processor_id() use in preemptible code")
Reported-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/all/20240827125335.GD4772@willie-the-truck/ [1]
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20241112113422.617954-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
A crash happened when testing cpu hotplug with respect to the memory
mapped ring buffers. It was assumed that the hot plug code was adding a
per CPU buffer that was already created that caused the crash. The real
problem was due to ref counting and was fixed by commit 2cf9733891a4
("ring-buffer: Fix refcount setting of boot mapped buffers").
When a per CPU buffer is created, it will not be created again even with
CPU hotplug, so the fix to not use CPU hotplug was a red herring. In fact,
it caused only the boot CPU buffer to be created, leaving the other CPU
per CPU buffers disabled.
Revert that change as it was not the culprit of the fix it was intended to
be.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241113230839.6c03640f@gandalf.local.home
Fixes: 912da2c384d5 ("ring-buffer: Do not have boot mapped buffers hook to CPU hotplug")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull rdma fixes from Jason Gunthorpe:
- Revert a change to the VLAN logic, this broke previously working ROCE
configurations
- Fix a memory leak on error unwinding in bnxt_re
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
Revert "RDMA/core: Fix ENODEV error for iWARP test over vlan"
RDMA/bnxt_re: Remove some dead code
RDMA/bnxt_re: Fix some error handling paths in bnxt_re_probe()
Driver Changes:
- Fix unlock on exec ioctl error path (Matthew Brost)
- Fix hibernation on LNL due to ggtt getting lost
(Matthew Brost / Matthew Auld)
- Fix missing runtime PM in OA release (Ashutosh)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/5ntcf2ssmmvo5dsf2mdcee4guwwmpbm3xrlufgt2pdfmznzjo3@62ygo3bxkock
The function ring_buffer_subbuf_order_set() updates each
ring_buffer_per_cpu and installs new sub buffers that match the requested
page order. This operation may be invoked concurrently with readers that
rely on some of the modified data, such as the head bit (RB_PAGE_HEAD), or
the ring_buffer_per_cpu.pages and reader_page pointers. However, no
exclusive access is acquired by ring_buffer_subbuf_order_set(). Modifying
the mentioned data while a reader also operates on them can then result in
incorrect memory access and various crashes.
Fix the problem by taking the reader_lock when updating a specific
ring_buffer_per_cpu in ring_buffer_subbuf_order_set().
Link: https://lore.kernel.org/linux-trace-kernel/20240715145141.5528-1-petr.pavlu@suse.com/
Link: https://lore.kernel.org/linux-trace-kernel/20241010195849.2f77cc3f@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20241011112850.17212b25@gandalf.local.home/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241015112440.26987-1-petr.pavlu@suse.com
Fixes: 8e7b58c27b3c ("ring-buffer: Just update the subbuffers when changing their allocation order")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull pmdomain fixes from Ulf Hansson:
"pmdomain core:
- Add GENPD_FLAG_DEV_NAME_FW flag to generate unique names
pmdomain providers:
- arm: Use FLAG_DEV_NAME_FW to ensure unique names
- imx93-blk-ctrl: Fix the remove path
arm_scmi/qcom-cpucp:
- Report duplicate OPPs as firmware bugs for arm_scmi
- Skip OPP duplicates for arm_scmi
- Mark the qcom-cpucp mailbox irq with IRQF_NO_SUSPEND flag"
* tag 'pmdomain-v6.12-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm:
mailbox: qcom-cpucp: Mark the irq with IRQF_NO_SUSPEND flag
firmware: arm_scmi: Report duplicate opps as firmware bugs
firmware: arm_scmi: Skip opp duplicates
pmdomain: imx93-blk-ctrl: correct remove path
pmdomain: arm: Use FLAG_DEV_NAME_FW to ensure unique names
pmdomain: core: Add GENPD_FLAG_DEV_NAME_FW flag
The citied commit in Fixes line caused to regression for udaddy [1]
application. It doesn't work over VLANs anymore.
Client:
ifconfig eth2 1.1.1.1
ip link add link eth2 name p0.3597 type vlan protocol 802.1Q id 3597
ip link set dev p0.3597 up
ip addr add 2.2.2.2/16 dev p0.3597
udaddy -S 847 -C 220 -c 2 -t 0 -s 2.2.2.3 -b 2.2.2.2
Server:
ifconfig eth2 1.1.1.3
ip link add link eth2 name p0.3597 type vlan protocol 802.1Q id 3597
ip link set dev p0.3597 up
ip addr add 2.2.2.3/16 dev p0.3597
udaddy -S 847 -C 220 -c 2 -t 0 -b 2.2.2.3
[1] https://github.com/linux-rdma/rdma-core/blob/master/librdmacm/examples/udaddy.c
Fixes: 5069d7e202f6 ("RDMA/core: Fix ENODEV error for iWARP test over vlan")
Reported-by: Leon Romanovsky <leonro@nvidia.com>
Closes: https://lore.kernel.org/all/20241110130746.GA48891@unreal
Link: https://patch.msgid.link/bb9d403419b2b9566da5b8bf0761fa8377927e49.1731401658.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
amd-drm-fixes-6.12-2024-11-14:
amdgpu:
- PSR fix
- Panel replay fixes
- DML fix
- vblank power fix
- Fix video caps
- SMU 14.0 fix
- GPUVM fix
- MES 12 fix
- APU carve out fix
- DC vbios fix
- NBIO fix
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241114143401.448210-1-alexander.deucher@amd.com
Fix the following drm_WARN:
[953.586396] xe 0000:00:02.0: [drm] Missing outer runtime PM protection
...
<4> [953.587090] ? xe_pm_runtime_get_noresume+0x8d/0xa0 [xe]
<4> [953.587208] guc_exec_queue_add_msg+0x28/0x130 [xe]
<4> [953.587319] guc_exec_queue_fini+0x3a/0x40 [xe]
<4> [953.587425] xe_exec_queue_destroy+0xb3/0xf0 [xe]
<4> [953.587515] xe_oa_release+0x9c/0xc0 [xe]
Suggested-by: John Harrison <john.c.harrison@intel.com>
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Fixes: e936f885f1e9 ("drm/xe/oa/uapi: Expose OA stream fd")
Cc: stable@vger.kernel.org
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241109032003.3093811-1-ashutosh.dixit@intel.com
(cherry picked from commit b107c63d2953907908fd0cafb0e543b3c3167b75)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Pull misc fixes from Andrew Morton:
"17 hotfixes. 9 are cc:stable. 13 are MM and 4 are non-MM.
The usual collection of singletons - please see the changelogs"
* tag 'mm-hotfixes-stable-2024-11-03-10-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm: multi-gen LRU: use {ptep,pmdp}_clear_young_notify()
mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats
mm, mmap: limit THP alignment of anonymous mappings to PMD-aligned sizes
mm: shrinker: avoid memleak in alloc_shrinker_info
.mailmap: update e-mail address for Eugen Hristev
vmscan,migrate: fix page count imbalance on node stats when demoting pages
mailmap: update Jarkko's email addresses
mm: allow set/clear page_type again
nilfs2: fix potential deadlock with newly created symlinks
Squashfs: fix variable overflow in squashfs_readpage_block
kasan: remove vmalloc_percpu test
tools/mm: -Werror fixes in page-types/slabinfo
mm, swap: avoid over reclaim of full clusters
mm: fix PSWPIN counter for large folios swap-in
mm: avoid VM_BUG_ON when try to map an anon large folio to zero page.
mm/codetag: fix null pointer check logic for ref and tag
mm/gup: stop leaking pinned pages in low memory conditions
A ring buffer which has its buffered mapped at boot up to fixed memory
should not be freed. Other buffers can be. The ref counting setup was
wrong for both. It made the not mapped buffers ref count have zero, and the
boot mapped buffer a ref count of 1. But an normally allocated buffer
should be 1, where it can be removed.
Keep the ref count of a normal boot buffer with its setup ref count (do
not decrement it), and increment the fixed memory boot mapped buffer's ref
count.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241011165224.33dd2624@gandalf.local.home
Fixes: e645535a954ad ("tracing: Add option to use memmapped memory for trace boot instance")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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