Linux kernel
============
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several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
Clone this repository
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Pull kvm fixes from Paolo Bonzini:
"ARM:
- Fix EL2 Stage-1 MMIO mappings where a random address was used
- Fix SMCCC function number comparison when the SVE hint is set
RISC-V:
- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of a missing extension
- Fix ISA_EXT register handling in get-reg-list test
- Fix filtering of AIA registers in get-reg-list test
x86:
- Fixes for TSC_AUX virtualization
- Stop zapping page tables asynchronously, since we don't zap them as
often as before"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: SVM: Do not use user return MSR support for virtualized TSC_AUX
KVM: SVM: Fix TSC_AUX virtualization setup
KVM: SVM: INTERCEPT_RDTSCP is never intercepted anyway
KVM: x86/mmu: Stop zapping invalidated TDP MMU roots asynchronously
KVM: x86/mmu: Do not filter address spaces in for_each_tdp_mmu_root_yield_safe()
KVM: x86/mmu: Open code leaf invalidation from mmu_notifier
KVM: riscv: selftests: Selectively filter-out AIA registers
KVM: riscv: selftests: Fix ISA_EXT register handling in get-reg-list
RISC-V: KVM: Fix riscv_vcpu_get_isa_ext_single() for missing extensions
RISC-V: KVM: Fix KVM_GET_REG_LIST API for ISA_EXT registers
KVM: selftests: Assert that vasprintf() is successful
KVM: arm64: nvhe: Ignore SVE hint in SMCCC function ID
KVM: arm64: Properly return allocated EL2 VA from hyp_alloc_private_va_range()
Pull tracing fixes from Steven Rostedt:
- Fix the "bytes" output of the per_cpu stat file
The tracefs/per_cpu/cpu*/stats "bytes" was giving bogus values as the
accounting was not accurate. It is suppose to show how many used
bytes are still in the ring buffer, but even when the ring buffer was
empty it would still show there were bytes used.
- Fix a bug in eventfs where reading a dynamic event directory (open)
and then creating a dynamic event that goes into that diretory screws
up the accounting.
On close, the newly created event dentry will get a "dput" without
ever having a "dget" done for it. The fix is to allocate an array on
dir open to save what dentries were actually "dget" on, and what ones
to "dput" on close.
* tag 'trace-v6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
eventfs: Remember what dentries were created on dir open
ring-buffer: Fix bytes info in per_cpu buffer stats
KVM/riscv fixes for 6.6, take #1
- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of a missing extension
- Fix ISA_EXT register handling in get-reg-list test
- Fix filtering of AIA registers in get-reg-list test
Pull cxl fixes from Dan Williams:
"A collection of regression fixes, bug fixes, and some small cleanups
to the Compute Express Link code.
The regressions arrived in the v6.5 dev cycle and missed the v6.6
merge window due to my personal absences this cycle. The most
important fixes are for scenarios where the CXL subsystem fails to
parse valid region configurations established by platform firmware.
This is important because agreement between OS and BIOS on the CXL
configuration is fundamental to implementing "OS native" error
handling, i.e. address translation and component failure
identification.
Other important fixes are a driver load error when the BIOS lets the
Linux PCI core handle AER events, but not CXL memory errors.
The other fixex might have end user impact, but for now are only known
to trigger in our test/emulation environment.
Summary:
- Fix multiple scenarios where platform firmware defined regions fail
to be assembled by the CXL core.
- Fix a spurious driver-load failure on platforms that enable OS
native AER, but not OS native CXL error handling.
- Fix a regression detecting "poison" commands when "security"
commands are also defined.
- Fix a cxl_test regression with the move to centralize CXL port
register enumeration in the CXL core.
- Miscellaneous small fixes and cleanups"
* tag 'cxl-fixes-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/acpi: Annotate struct cxl_cxims_data with __counted_by
cxl/port: Fix cxl_test register enumeration regression
cxl/region: Refactor granularity select in cxl_port_setup_targets()
cxl/region: Match auto-discovered region decoders by HPA range
cxl/mbox: Fix CEL logic for poison and security commands
cxl/pci: Replace host_bridge->native_aer with pcie_aer_is_native()
PCI/AER: Export pcie_aer_is_native()
cxl/pci: Fix appropriate checking for _OSC while handling CXL RAS registers
Using the following code with libtracefs:
int dfd;
// create the directory events/kprobes/kp1
tracefs_kprobe_raw(NULL, "kp1", "schedule_timeout", "time=$arg1");
// Open the kprobes directory
dfd = tracefs_instance_file_open(NULL, "events/kprobes", O_RDONLY);
// Do a lookup of the kprobes/kp1 directory (by looking at enable)
tracefs_file_exists(NULL, "events/kprobes/kp1/enable");
// Now create a new entry in the kprobes directory
tracefs_kprobe_raw(NULL, "kp2", "schedule_hrtimeout", "expires=$arg1");
// Do another lookup to create the dentries
tracefs_file_exists(NULL, "events/kprobes/kp2/enable"))
// Close the directory
close(dfd);
What happened above, the first open (dfd) will call
dcache_dir_open_wrapper() that will create the dentries and up their ref
counts.
Now the creation of "kp2" will add another dentry within the kprobes
directory.
Upon the close of dfd, eventfs_release() will now do a dput for all the
entries in kprobes. But this is where the problem lies. The open only
upped the dentry of kp1 and not kp2. Now the close is decrementing both
kp1 and kp2, which causes kp2 to get a negative count.
Doing a "trace-cmd reset" which deletes all the kprobes cause the kernel
to crash! (due to the messed up accounting of the ref counts).
To solve this, save all the dentries that are opened in the
dcache_dir_open_wrapper() into an array, and use this array to know what
dentries to do a dput on in eventfs_release().
Since the dcache_dir_open_wrapper() calls dcache_dir_open() which uses the
file->private_data, we need to also add a wrapper around dcache_readdir()
that uses the cursor assigned to the file->private_data. This is because
the dentries need to also be saved in the file->private_data. To do this
create the structure:
struct dentry_list {
void *cursor;
struct dentry **dentries;
};
Which will hold both the cursor and the dentries. Some shuffling around is
needed to make sure that dcache_dir_open() and dcache_readdir() only see
the cursor.
Link: https://lore.kernel.org/linux-trace-kernel/20230919211804.230edf1e@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20230922163446.1431d4fa@gandalf.local.home
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ajay Kaher <akaher@vmware.com>
Fixes: 63940449555e7 ("eventfs: Implement eventfs lookup, read, open functions")
Reported-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When the TSC_AUX MSR is virtualized, the TSC_AUX value is swap type "B"
within the VMSA. This means that the guest value is loaded on VMRUN and
the host value is restored from the host save area on #VMEXIT.
Since the value is restored on #VMEXIT, the KVM user return MSR support
for TSC_AUX can be replaced by populating the host save area with the
current host value of TSC_AUX. And, since TSC_AUX is not changed by Linux
post-boot, the host save area can be set once in svm_hardware_enable().
This eliminates the two WRMSR instructions associated with the user return
MSR support.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <d381de38eb0ab6c9c93dda8503b72b72546053d7.1694811272.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently the AIA ONE_REG registers are reported by get-reg-list
as new registers for various vcpu_reg_list configs whenever Ssaia
is available on the host because Ssaia extension can only be
disabled by Smstateen extension which is not always available.
To tackle this, we should filter-out AIA ONE_REG registers only
when Ssaia can't be disabled for a VCPU.
Fixes: 477069398ed6 ("KVM: riscv: selftests: Add get-reg-list test")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Pull gpio fixes from Bartosz Golaszewski:
- fix an invalid usage of __free(kfree) leading to kfreeing an
ERR_PTR()
- fix an irq domain leak in gpio-tb10x
- MAINTAINERS update
* tag 'gpio-fixes-for-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: sim: fix an invalid __free() usage
gpio: tb10x: Fix an error handling path in tb10x_gpio_probe()
MAINTAINERS: gpio-regmap: make myself a maintainer of it
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 checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct cxl_cxims_data.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-cxl@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230922175319.work.096-kees@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The 'bytes' info in file 'per_cpu/cpu<X>/stats' means the number of
bytes in cpu buffer that have not been consumed. However, currently
after consuming data by reading file 'trace_pipe', the 'bytes' info
was not changed as expected.
# cat per_cpu/cpu0/stats
entries: 0
overrun: 0
commit overrun: 0
bytes: 568 <--- 'bytes' is problematical !!!
oldest event ts: 8651.371479
now ts: 8653.912224
dropped events: 0
read events: 8
The root cause is incorrect stat on cpu_buffer->read_bytes. To fix it:
1. When stat 'read_bytes', account consumed event in rb_advance_reader();
2. When stat 'entries_bytes', exclude the discarded padding event which
is smaller than minimum size because it is invisible to reader. Then
use rb_page_commit() instead of BUF_PAGE_SIZE at where accounting for
page-based read/remove/overrun.
Also correct the comments of ring_buffer_bytes_cpu() in this patch.
Link: https://lore.kernel.org/linux-trace-kernel/20230921125425.1708423-1-zhengyejian1@huawei.com
Cc: stable@vger.kernel.org
Fixes: c64e148a3be3 ("trace: Add ring buffer stats to measure rate of events")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The checks for virtualizing TSC_AUX occur during the vCPU reset processing
path. However, at the time of initial vCPU reset processing, when the vCPU
is first created, not all of the guest CPUID information has been set. In
this case the RDTSCP and RDPID feature support for the guest is not in
place and so TSC_AUX virtualization is not established.
This continues for each vCPU created for the guest. On the first boot of
an AP, vCPU reset processing is executed as a result of an APIC INIT
event, this time with all of the guest CPUID information set, resulting
in TSC_AUX virtualization being enabled, but only for the APs. The BSP
always sees a TSC_AUX value of 0 which probably went unnoticed because,
at least for Linux, the BSP TSC_AUX value is 0.
Move the TSC_AUX virtualization enablement out of the init_vmcb() path and
into the vcpu_after_set_cpuid() path to allow for proper initialization of
the support after the guest CPUID information has been set.
With the TSC_AUX virtualization support now in the vcpu_set_after_cpuid()
path, the intercepts must be either cleared or set based on the guest
CPUID input.
Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <4137fbcb9008951ab5f0befa74a0399d2cce809a.1694811272.git.thomas.lendacky@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Same set of ISA_EXT registers are not present on all host because
ISA_EXT registers are visible to the KVM user space based on the
ISA extensions available on the host. Also, disabling an ISA
extension using corresponding ISA_EXT register does not affect
the visibility of the ISA_EXT register itself.
Based on the above, we should filter-out all ISA_EXT registers.
Fixes: 477069398ed6 ("KVM: riscv: selftests: Add get-reg-list test")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Pull misc fixes from Andrew Morton:
"13 hotfixes, 10 of which pertain to post-6.5 issues. The other three
are cc:stable"
* tag 'mm-hotfixes-stable-2023-09-23-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
proc: nommu: fix empty /proc/<pid>/maps
filemap: add filemap_map_order0_folio() to handle order0 folio
proc: nommu: /proc/<pid>/maps: release mmap read lock
mm: memcontrol: fix GFP_NOFS recursion in memory.high enforcement
pidfd: prevent a kernel-doc warning
argv_split: fix kernel-doc warnings
scatterlist: add missing function params to kernel-doc
selftests/proc: fixup proc-empty-vm test after KSM changes
revert "scripts/gdb/symbols: add specific ko module load command"
selftests: link libasan statically for tests with -fsanitize=address
task_work: add kerneldoc annotation for 'data' argument
mm: page_alloc: fix CMA and HIGHATOMIC landing on the wrong buddy list
sh: mm: re-add lost __ref to ioremap_prot() to fix modpost warning
gpio_sim_make_line_names() returns NULL or ERR_PTR() so we must not use
__free(kfree) on the returned address. Split this function into two, one
that determines the size of the "gpio-line-names" array to allocate and
one that actually sets the names at correct offsets. The allocation and
assignment of the managed pointer happens in between.
Fixes: 3faf89f27aab ("gpio: sim: simplify code with cleanup helpers")
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Closes: https://lore.kernel.org/all/07c32bf1-6c1a-49d9-b97d-f0ae4a2b42ab@p183/
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
The cxl_test unit test environment models a CXL topology for
sysfs/user-ABI regression testing. It uses interface mocking via the
"--wrap=" linker option to redirect cxl_core routines that parse
hardware registers with versions that just publish objects, like
devm_cxl_enumerate_decoders().
Starting with:
Commit 19ab69a60e3b ("cxl/port: Store the port's Component Register mappings in struct cxl_port")
...port register enumeration is moved into devm_cxl_add_port(). This
conflicts with the "cxl_test avoids emulating registers stance" so
either the port code needs to be refactored (too violent), or modified
so that register enumeration is skipped on "fake" cxl_test ports
(annoying, but straightforward).
This conflict has happened previously and the "check for platform
device" workaround to avoid instrusive refactoring was deployed in those
scenarios. In general, refactoring should only benefit production code,
test code needs to remain minimally instrusive to the greatest extent
possible.
This was missed previously because it may sometimes just cause warning
messages to be emitted, but it can also cause test failures. The
backport to -stable is only nice to have for clean cxl_test runs.
Fixes: 19ab69a60e3b ("cxl/port: Store the port's Component Register mappings in struct cxl_port")
Cc: stable@vger.kernel.org
Reported-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/169476525052.1013896.6235102957693675187.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>