At a commit 673249124304 ("firewire: core: option to log bus reset
initiation"), some kernel log messages were added to trace initiation of
bus reset. The kernel log messages are really helpful, while nowadays it
is not preferable just for debugging purpose. For the purpose, Linux
kernel tracepoints is more preferable.
This commit adds some alternative tracepoints events.
Link: https://lore.kernel.org/r/20240501073238.72769-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In the former commits, the spurious interrupt events are suppressed as
possible, by unset bus-reset event from the set of handled irq. The change
was written with the less-intrusive style, thus it firstly works at the
second time to handle the event. But it is slightly inconvenient.
This commit adds the event for the initial set of irq to handle. As a
result, the event can be handled even if it is the first time. The change
has a benefit that the OHCI_PARAM_DEBUG_BUSRESETS bit in debug module
parameter is always effective.
Tested-by: Adam Goldman <adamg@pobox.com>
Link: https://lore.kernel.org/r/20240501073238.72769-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
At the former commit, a pair of tracepoints events is added to trace
asynchronous outbound phy packet. This commit adds a tracepoints event
to trace inbound phy packet. It includes transaction status as well as
the content of phy packet.
This is an example for Remote Reply Packet as a response to Remote Access
Packet sent by lsfirewirephy command in linux-firewire-utils:
async_phy_inbound: \
packet=0xffff955fc02b4e10 generation=1 status=1 timestamp=0x0619 \
first_quadlet=0x001c8208 second_quadlet=0xffe37df7
Link: https://lore.kernel.org/r/20240430001404.734657-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In IEEE 1394 bus, the type of asynchronous packet without any offset to
node address space is called as phy packet. The destination of packet is
IEEE 1394 phy itself. This type of packet is used for several purposes,
mainly for selfID at the state of bus reset, to force selection of root
node, and to adjust gap count.
This commit adds tracepoints events for the type of asynchronous outbound
packet. Like asynchronous outbound transaction packets, a pair of events
are added to trace initiation and completion of transmission.
In the case that the phy packet is sent by kernel API, the match between
the initiation and completion is not so easy, since the data of
'struct fw_packet' is allocated statically. In the case that it is sent by
userspace applications via cdev, the match is easy, since the data is
allocated per each.
This example is for Remote Access Packet by lsfirewirephy command in
linux-firewire-utils:
async_phy_outbound_initiate: \
packet=0xffff89fb34e42e78 generation=1 first_quadlet=0x00148200 \
second_quadlet=0xffeb7dff
async_phy_outbound_complete: \
packet=0xffff89fb34e42e78 generation=1 status=1 timestamp=0x0619
Link: https://lore.kernel.org/r/20240430001404.734657-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In a view of core transaction service, the asynchronous outbound response
consists of two stages; initiation and completion.
This commit adds a pair of events for the asynchronous outbound response.
The following example is for asynchronous write quadlet request as IEC
61883-1 FCP response to node 0xffc1.
async_response_outbound_initiate: \
transaction=0xffff89fa08cf16c0 generation=4 scode=2 dst_id=0xffc1 \
tlabel=25 tcode=2 src_id=0xffc0 rcode=0 \
header={0xffc16420,0xffc00000,0x0,0x0} data={}
async_response_outbound_complete: \
transaction=0xffff89fa08cf16c0 generation=4 scode=2 status=1 \
timestamp=0x0000
Link: https://lore.kernel.org/r/20240429043218.609398-6-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
This commit adds an event for asynchronous inbound request.
The following example is for asynchronous block write request as IEC
61883-1 FCP request from node 0xffc1.
async_request_inbound: \
transaction=0xffff89fa08cf16c0 generation=4 scode=2 status=2 \
timestamp=0x00b3 dst_id=0xffc0 tlabel=19 tcode=1 src_id=0xffc1 \
offset=0xfffff0000d00 header={0xffc04d10,0xffc1ffff,0xf0000d00,0x80000} \
data={0x19ff08,0xffff0090}
Link: https://lore.kernel.org/r/20240429043218.609398-5-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In the transaction of IEEE 1394, the node to receive the asynchronous
request transfers any response packet to the requester except for the
unified transaction.
This commit adds an event for the inbound packet. Note that the code to
decode the packet header is moved, against the note about the sanity
check.
The following example is for asynchronous lock response with
compare_and_swap code.
async_response_inbound: \
transaction=0xffff955fc6a07a10 generation=5 scode=2 status=1 \
timestamp=0x0089 dst_id=0xffc1 tlabel=54 tcode=11 src_id=0xffc0 \
rcode=0 header={0xffc1d9b0,0xffc00000,0x0,0x40002} data={0x50800080}
Link: https://lore.kernel.org/r/20240429043218.609398-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In a view of core transaction service, the asynchronous outbound request
consists of two stages; initiation and completion. This commit adds a pair
of event for them.
The following example is for asynchronous lock request with compare_swap
code to offset 0x'ffff'f000'0904 in node 0xffc0.
async_request_outbound_initiate: \
transaction=0xffff955fc6a07a10 generation=5 scode=2 dst_id=0xffc0 \
tlabel=54 tcode=9 src_id=0xffc1 offset=0xfffff0000904 \
header={0xffc0d990,0xffc1ffff,0xf0000904,0x80002}
data={0x80,0x940181}
async_request_outbound_complete: \
transaction=0xffff955fc6a07a10 generation=5 scode=2 status=2 \
timestamp=0xd887
Link: https://lore.kernel.org/r/20240429043218.609398-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
In both core and 1394 OHCI driver, some hard-coded values and macros are
used to serialize/deserialize the header of asynchronous packets. It is
inconvenient to reuse them.
This commit adds some helper inline functions with their tests for the
purpose.
Link: https://lore.kernel.org/r/20240428071347.409202-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
The usage of the pair of pci_enable_msi() and pci_disable_msi() is
deprecated.
This commit uses the preferred pair of API for the purpose. The call of
pci_alloc_irq_vectors() can have a subeffect to change the return value
of pci_dev_msi_enabled().
Link: https://lore.kernel.org/r/20240331135037.191479-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/ZgIrOuR3JI/jzqoH@neat
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Add a debug parameter to firewire-core, analogous to the one in
firewire-ohci. When this is set to 1, log when we schedule, delay, or
initiate a bus reset. Since FireWire bus resets can originate from any
node on the bus, specific logging of the resets we initiate provides
additional insight.
Signed-off-by: Adam Goldman <adamg@pobox.com>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
epoll can call out to vfs_poll() with a file pointer that may race with
the last 'fput()'. That would make f_count go down to zero, and while
the ep->mtx locking means that the resulting file pointer tear-down will
be blocked until the poll returns, it means that f_count is already
dead, and any use of it won't actually get a reference to the file any
more: it's dead regardless.
Make sure we have a valid ref on the file pointer before we call down to
vfs_poll() from the epoll routines.
Link: https://lore.kernel.org/lkml/0000000000002d631f0615918f1e@google.com/
Reported-by: syzbot+045b454ab35fd82a35fb@syzkaller.appspotmail.com
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull EDAC fixes from Borislav Petkov:
- Fix error logging and check user-supplied data when injecting an
error in the versal EDAC driver
* tag 'edac_urgent_for_v6.9_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/versal: Do not log total error counts
EDAC/versal: Check user-supplied data before injecting an error
EDAC/versal: Do not register for NOC errors
Pull powerpc fixes from Michael Ellerman:
- Fix incorrect delay handling in the plpks (keystore) code
- Fix a panic when an LPAR boots with a frozen PE
Thanks to Andrew Donnellan, Gaurav Batra, Nageswara R Sastry, and Nayna
Jain.
* tag 'powerpc-6.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/pseries/iommu: LPAR panics during boot up with a frozen PE
powerpc/pseries: make max polling consistent for longer H_CALLs
Pull misc x86 fixes from Ingo Molnar:
- Remove the broken vsyscall emulation code from
the page fault code
- Fix kexec crash triggered by certain SEV RMP
table layouts
- Fix unchecked MSR access error when disabling
the x2APIC via iommu=off
* tag 'x86-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Remove broken vsyscall emulation code from the page fault code
x86/apic: Don't access the APIC when disabling x2APIC
x86/sev: Add callback to apply RMP table fixups for kexec
x86/e820: Add a new e820 table update helper
Pull irq fix from Ingo Molnar:
"Fix suspicious RCU usage in __do_softirq()"
* tag 'irq-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
softirq: Fix suspicious RCU usage in __do_softirq()
Pull char/misc driver fixes from Greg KH:
"Here are some small char/misc/other driver fixes and new device ids
for 6.9-rc7 that resolve some reported problems.
Included in here are:
- iio driver fixes
- mei driver fix and new device ids
- dyndbg bugfix
- pvpanic-pci driver bugfix
- slimbus driver bugfix
- fpga new device id
All have been in linux-next with no reported problems"
* tag 'char-misc-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
slimbus: qcom-ngd-ctrl: Add timeout for wait operation
dyndbg: fix old BUG_ON in >control parser
misc/pvpanic-pci: register attributes via pci_driver
fpga: dfl-pci: add PCI subdevice ID for Intel D5005 card
mei: me: add lunar lake point M DID
mei: pxp: match against PCI_CLASS_DISPLAY_OTHER
iio:imu: adis16475: Fix sync mode setting
iio: accel: mxc4005: Reset chip on probe() and resume()
iio: accel: mxc4005: Interrupt handling fixes
dt-bindings: iio: health: maxim,max30102: fix compatible check
iio: pressure: Fixes SPI support for BMP3xx devices
iio: pressure: Fixes BME280 SPI driver data
Pull USB driver fixes from Greg KH:
"Here are some small USB driver fixes for reported problems for
6.9-rc7. Included in here are:
- usb core fixes for found issues
- typec driver fixes for reported problems
- usb gadget driver fixes for reported problems
- xhci build fixes
- dwc3 driver fixes for reported issues
All of these have been in linux-next this past week with no reported
problems"
* tag 'usb-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: typec: tcpm: Check for port partner validity before consuming it
usb: typec: tcpm: enforce ready state when queueing alt mode vdm
usb: typec: tcpm: unregister existing source caps before re-registration
usb: typec: tcpm: clear pd_event queue in PORT_RESET
usb: typec: tcpm: queue correct sop type in tcpm_queue_vdm_unlocked
usb: Fix regression caused by invalid ep0 maxpacket in virtual SuperSpeed device
usb: ohci: Prevent missed ohci interrupts
usb: typec: qcom-pmic: fix pdphy start() error handling
usb: typec: qcom-pmic: fix use-after-free on late probe errors
usb: gadget: f_fs: Fix a race condition when processing setup packets.
USB: core: Fix access violation during port device removal
usb: dwc3: core: Prevent phy suspend during init
usb: xhci-plat: Don't include xhci.h
usb: gadget: uvc: use correct buffer size when parsing configfs lists
usb: gadget: composite: fix OS descriptors w_value logic
usb: gadget: f_fs: Fix race between aio_cancel() and AIO request complete
Pull input fixes from Dmitry Torokhov:
- a new ID for ASUS ROG RAIKIRI controllers added to xpad driver
- amimouse driver structure annotated with __refdata to prevent section
mismatch warnings.
* tag 'input-for-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: amimouse - mark driver struct with __refdata to prevent section mismatch
Input: xpad - add support for ASUS ROG RAIKIRI
Pull probes fix from Masami Hiramatsu:
- probe-events: Fix memory leak in parsing probe argument.
There is a memory leak (forget to free an allocated buffer) in a
memory allocation failure path. Fix it to jump to the correct error
handling code.
* tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/probes: Fix memory leak in traceprobe_parse_probe_arg_body()
Pull tracing and tracefs fixes from Steven Rostedt:
- Fix RCU callback of freeing an eventfs_inode.
The freeing of the eventfs_inode from the kref going to zero freed
the contents of the eventfs_inode and then used kfree_rcu() to free
the inode itself. But the contents should also be protected by RCU.
Switch to a call_rcu() that calls a function to free all of the
eventfs_inode after the RCU synchronization.
- The tracing subsystem maps its own descriptor to a file represented
by eventfs. The freeing of this descriptor needs to know when the
last reference of an eventfs_inode is released, but currently there
is no interface for that.
Add a "release" callback to the eventfs_inode entry array that allows
for freeing of data that can be referenced by the eventfs_inode being
opened. Then increment the ref counter for this descriptor when the
eventfs_inode file is created, and decrement/free it when the last
reference to the eventfs_inode is released and the file is removed.
This prevents races between freeing the descriptor and the opening of
the eventfs file.
- Fix the permission processing of eventfs.
The change to make the permissions of eventfs default to the mount
point but keep track of when changes were made had a side effect that
could cause security concerns. When the tracefs is remounted with a
given gid or uid, all the files within it should inherit that gid or
uid. But if the admin had changed the permission of some file within
the tracefs file system, it would not get updated by the remount.
This caused the kselftest of file permissions to fail the second time
it is run. The first time, all changes would look fine, but the
second time, because the changes were "saved", the remount did not
reset them.
Create a link list of all existing tracefs inodes, and clear the
saved flags on them on a remount if the remount changes the
corresponding gid or uid fields.
This also simplifies the code by removing the distinction between the
toplevel eventfs and an instance eventfs. They should both act the
same. They were different because of a misconception due to the
remount not resetting the flags. Now that remount resets all the
files and directories to default to the root node if a uid/gid is
specified, it makes the logic simpler to implement.
* tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
eventfs: Have "events" directory get permissions from its parent
eventfs: Do not treat events directory different than other directories
eventfs: Do not differentiate the toplevel events directory
tracefs: Still use mount point as default permissions for instances
tracefs: Reset permissions on remount if permissions are options
eventfs: Free all of the eventfs_inode after RCU
eventfs/tracing: Add callback for release of an eventfs_inode
Pull dma-mapping fix from Christoph Hellwig:
- fix the combination of restricted pools and dynamic swiotlb
(Will Deacon)
* tag 'dma-mapping-6.9-2024-05-04' of git://git.infradead.org/users/hch/dma-mapping:
swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y
Pull clk fixes from Stephen Boyd:
"A handful of clk driver fixes:
- Avoid a deadlock in the Qualcomm clk driver by making the regulator
which supplies the GDSC optional
- Restore RPM clks on Qualcomm msm8976 by setting num_clks
- Fix Allwinner H6 CPU rate changing logic to avoid system crashes by
temporarily reparenting the CPU clk to something that isn't being
changed
- Set a MIPI PLL min/max rate on Allwinner A64 to fix blank screens
on some devices
- Revert back to of_match_device() in the Samsung clkout driver to
get the match data based on the parent device's compatible string"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: samsung: Revert "clk: Use device_get_match_data()"
clk: sunxi-ng: a64: Set minimum and maximum rate for PLL-MIPI
clk: sunxi-ng: common: Support minimum and maximum rate
clk: sunxi-ng: h6: Reparent CPUX during PLL CPUX rate change
clk: qcom: smd-rpm: Restore msm8976 num_clk
clk: qcom: gdsc: treat optional supplies as optional
The events directory gets its permissions from the root inode. But this
can cause an inconsistency if the instances directory changes its
permissions, as the permissions of the created directories under it should
inherit the permissions of the instances directory when directories under
it are created.
Currently the behavior is:
# cd /sys/kernel/tracing
# chgrp 1002 instances
# mkdir instances/foo
# ls -l instances/foo
[..]
-r--r----- 1 root lkp 0 May 1 18:55 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 18:55 current_tracer
-rw-r----- 1 root lkp 0 May 1 18:55 error_log
drwxr-xr-x 1 root root 0 May 1 18:55 events
--w------- 1 root lkp 0 May 1 18:55 free_buffer
drwxr-x--- 2 root lkp 0 May 1 18:55 options
drwxr-x--- 10 root lkp 0 May 1 18:55 per_cpu
-rw-r----- 1 root lkp 0 May 1 18:55 set_event
All the files and directories under "foo" has the "lkp" group except the
"events" directory. That's because its getting its default value from the
mount point instead of its parent.
Have the "events" directory make its default value based on its parent's
permissions. That now gives:
# ls -l instances/foo
[..]
-rw-r----- 1 root lkp 0 May 1 21:16 buffer_subbuf_size_kb
-r--r----- 1 root lkp 0 May 1 21:16 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 21:16 current_tracer
-rw-r----- 1 root lkp 0 May 1 21:16 error_log
drwxr-xr-x 1 root lkp 0 May 1 21:16 events
--w------- 1 root lkp 0 May 1 21:16 free_buffer
drwxr-x--- 2 root lkp 0 May 1 21:16 options
drwxr-x--- 10 root lkp 0 May 1 21:16 per_cpu
-rw-r----- 1 root lkp 0 May 1 21:16 set_event
Link: https://lore.kernel.org/linux-trace-kernel/20240502200906.161887248@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Treat the events directory the same as other directories when it comes to
permissions. The events directory was considered different because it's
dentry is persistent, whereas the other directory dentries are created
when accessed. But the way tracefs now does its ownership by using the
root dentry's permissions as the default permissions, the events directory
can get out of sync when a remount is performed setting the group and user
permissions.
Remove the special case for the events directory on setting the
attributes. This allows the updates caused by remount to work properly as
well as simplifies the code.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200906.002923579@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If the instances directory's permissions were never change, then have it
and its children use the mount point permissions as the default.
Currently, the permissions of instance directories are determined by the
instance directory's permissions itself. But if the tracefs file system is
remounted and changes the permissions, the instance directory and its
children should use the new permission.
But because both the instance directory and its children use the instance
directory's inode for permissions, it misses the update.
To demonstrate this:
# cd /sys/kernel/tracing/
# mkdir instances/foo
# ls -ld instances/foo
drwxr-x--- 5 root root 0 May 1 19:07 instances/foo
# ls -ld instances
drwxr-x--- 3 root root 0 May 1 18:57 instances
# ls -ld current_tracer
-rw-r----- 1 root root 0 May 1 18:57 current_tracer
# mount -o remount,gid=1002 .
# ls -ld instances
drwxr-x--- 3 root root 0 May 1 18:57 instances
# ls -ld instances/foo/
drwxr-x--- 5 root root 0 May 1 19:07 instances/foo/
# ls -ld current_tracer
-rw-r----- 1 root lkp 0 May 1 18:57 current_tracer
Notice that changing the group id to that of "lkp" did not affect the
instances directory nor its children. It should have been:
# ls -ld current_tracer
-rw-r----- 1 root root 0 May 1 19:19 current_tracer
# ls -ld instances/foo/
drwxr-x--- 5 root root 0 May 1 19:25 instances/foo/
# ls -ld instances
drwxr-x--- 3 root root 0 May 1 19:19 instances
# mount -o remount,gid=1002 .
# ls -ld current_tracer
-rw-r----- 1 root lkp 0 May 1 19:19 current_tracer
# ls -ld instances
drwxr-x--- 3 root lkp 0 May 1 19:19 instances
# ls -ld instances/foo/
drwxr-x--- 5 root lkp 0 May 1 19:25 instances/foo/
Where all files were updated by the remount gid update.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.686838327@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's an inconsistency with the way permissions are handled in tracefs.
Because the permissions are generated when accessed, they default to the
root inode's permission if they were never set by the user. If the user
sets the permissions, then a flag is set and the permissions are saved via
the inode (for tracefs files) or an internal attribute field (for
eventfs).
But if a remount happens that specify the permissions, all the files that
were not changed by the user gets updated, but the ones that were are not.
If the user were to remount the file system with a given permission, then
all files and directories within that file system should be updated.
This can cause security issues if a file's permission was updated but the
admin forgot about it. They could incorrectly think that remounting with
permissions set would update all files, but miss some.
For example:
# cd /sys/kernel/tracing
# chgrp 1002 current_tracer
# ls -l
[..]
-rw-r----- 1 root root 0 May 1 21:25 buffer_size_kb
-rw-r----- 1 root root 0 May 1 21:25 buffer_subbuf_size_kb
-r--r----- 1 root root 0 May 1 21:25 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 21:25 current_tracer
-rw-r----- 1 root root 0 May 1 21:25 dynamic_events
-r--r----- 1 root root 0 May 1 21:25 dyn_ftrace_total_info
-r--r----- 1 root root 0 May 1 21:25 enabled_functions
Where current_tracer now has group "lkp".
# mount -o remount,gid=1001 .
# ls -l
-rw-r----- 1 root tracing 0 May 1 21:25 buffer_size_kb
-rw-r----- 1 root tracing 0 May 1 21:25 buffer_subbuf_size_kb
-r--r----- 1 root tracing 0 May 1 21:25 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 21:25 current_tracer
-rw-r----- 1 root tracing 0 May 1 21:25 dynamic_events
-r--r----- 1 root tracing 0 May 1 21:25 dyn_ftrace_total_info
-r--r----- 1 root tracing 0 May 1 21:25 enabled_functions
Everything changed but the "current_tracer".
Add a new link list that keeps track of all the tracefs_inodes which has
the permission flags that tell if the file/dir should use the root inode's
permission or not. Then on remount, clear all the flags so that the
default behavior of using the root inode's permission is done for all
files and directories.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.529542160@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Synthetic events create and destroy tracefs files when they are created
and removed. The tracing subsystem has its own file descriptor
representing the state of the events attached to the tracefs files.
There's a race between the eventfs files and this file descriptor of the
tracing system where the following can cause an issue:
With two scripts 'A' and 'B' doing:
Script 'A':
echo "hello int aaa" > /sys/kernel/tracing/synthetic_events
while :
do
echo 0 > /sys/kernel/tracing/events/synthetic/hello/enable
done
Script 'B':
echo > /sys/kernel/tracing/synthetic_events
Script 'A' creates a synthetic event "hello" and then just writes zero
into its enable file.
Script 'B' removes all synthetic events (including the newly created
"hello" event).
What happens is that the opening of the "enable" file has:
{
struct trace_event_file *file = inode->i_private;
int ret;
ret = tracing_check_open_get_tr(file->tr);
[..]
But deleting the events frees the "file" descriptor, and a "use after
free" happens with the dereference at "file->tr".
The file descriptor does have a reference counter, but there needs to be a
way to decrement it from the eventfs when the eventfs_inode is removed
that represents this file descriptor.
Add an optional "release" callback to the eventfs_entry array structure,
that gets called when the eventfs file is about to be removed. This allows
for the creating on the eventfs file to increment the tracing file
descriptor ref counter. When the eventfs file is deleted, it can call the
release function that will call the put function for the tracing file
descriptor.
This will protect the tracing file from being freed while a eventfs file
that references it is being opened.
Link: https://lore.kernel.org/linux-trace-kernel/20240426073410.17154-1-Tze-nan.Wu@mediatek.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240502090315.448cba46@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Tze-nan wu <Tze-nan.Wu@mediatek.com>
Tested-by: Tze-nan Wu (吳澤南) <Tze-nan.Wu@mediatek.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Pull cxl fix from Dave Jiang:
"Add missing RCH support for endpoint access_coordinate calculation.
A late bug was reported by Robert Richter that the Restricted CXL Host
(RCH) support was missing in the CXL endpoint access_coordinate
calculation.
The missing support causes the topology iterator to stumble over a
NULL pointer and triggers a kernel OOPS on a platform with CXL 1.1
support.
The fix bypasses RCH topology as the access_coordinate calculation is
not necessary since RCH does not support hotplug and the memory region
exported should be covered by the HMAT table already.
A unit test is also added to cxl_test to check against future
regressions on the topology iterator"
* tag 'cxl-fixes-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl: Fix cxl_endpoint_get_perf_coordinate() support for RCH
Pull xen fixes from Juergen Gross:
"Two fixes when running as Xen PV guests for issues introduced in the
6.9 merge window, both related to apic id handling"
* tag 'for-linus-6.9a-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: return a sane initial apic id when running as PV guest
x86/xen/smp_pv: Register the boot CPU APIC properly
Pull EFI fix from Ard Biesheuvel:
"This works around a shortcoming in the memory acceptation API, which
may apparently hog the CPU for long enough to trigger the softlockup
watchdog.
Note that this only affects confidential VMs running under the Intel
TDX hypervisor, which is why I accepted this for now, but this should
obviously be fixed properly in the future"
* tag 'efi-urgent-for-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
efi/unaccepted: touch soft lockup during memory accept
