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2022-11-21Merge tag 'memory-controller-drv-6.2-2' of ↵Arnd Bergmann
https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl into soc/drivers Memory controller drivers for v6.2, part two 1. ARM PL353: document PL354 in bindings. 2. TI/OMAP GPMC: allow setting wait-pin polarity. * tag 'memory-controller-drv-6.2-2' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl: memory: omap-gpmc: fix coverity issue "Control flow issues" dt-bindings: memory-controllers: ti,gpmc: add wait-pin polarity memory: omap-gpmc: wait pin additions MAINTAINERS: arm,pl353-smc: correct dt-binding path dt-bindings: memory-controllers: arm,pl353-smc: Extend to support 'arm,pl354' SMC Link: https://lore.kernel.org/r/20221116093509.19657-1-krzysztof.kozlowski@linaro.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-11-21pinconf-generic: fix style issues in pin_config_param docNiyas Sait
Fixes following issues introduced in a previous commit to clarify values for pin config pull up and down types. - replace spaces with tabs to be consistent with rest of the doc - use capitalization for unit (ohms -> Ohms) Signed-off-by: Niyas Sait <niyas.sait@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20221117123542.1154252-1-niyas.sait@linaro.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2022-11-21mtd: spi-nor: remember full JEDEC flash IDMichael Walle
At the moment, we print the JEDEC ID that is stored in our database. The generic flash support won't have such an entry in our database. To find out the JEDEC ID later we will have to cache it. There is also another advantage: If the flash is found in the database, the ID could be truncated because the ID of the entry is used which can be shorter. Some flashes still holds valuable information in the bytes after the JEDEC ID and come in handy during debugging of when coping with INFO6() entries. These are not accessible for now. Save a copy of the ID bytes after reading and display it via debugfs. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Reviewed-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com> Link: https://lore.kernel.org/r/20220810220654.1297699-4-michael@walle.cc
2022-11-21Merge branch 'slab/for-6.2/alloc_size' into slab/for-nextVlastimil Babka
Two patches from Kees Cook [1]: These patches work around a deficiency in GCC (>=11) and Clang (<16) where the __alloc_size attribute does not apply to inlines. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96503 This manifests as reduced overflow detection coverage for many allocation sites under CONFIG_FORTIFY_SOURCE=y, where the allocation size was not actually being propagated to __builtin_dynamic_object_size(). [1] https://lore.kernel.org/all/20221118034713.gonna.754-kees@kernel.org/
2022-11-21Merge branch 'slab/for-6.2/kmalloc_redzone' into slab/for-nextVlastimil Babka
kmalloc() redzone improvements by Feng Tang From cover letter [1]: kmalloc's API family is critical for mm, and one of its nature is that it will round up the request size to a fixed one (mostly power of 2). When user requests memory for '2^n + 1' bytes, actually 2^(n+1) bytes could be allocated, so there is an extra space than what is originally requested. This patchset tries to extend the redzone sanity check to the extra kmalloced buffer than requested, to better detect un-legitimate access to it. (depends on SLAB_STORE_USER & SLAB_RED_ZONE) [1] https://lore.kernel.org/all/20221021032405.1825078-1-feng.tang@intel.com/
2022-11-21Merge branch 'slab/for-6.2/cleanups' into slab/for-nextVlastimil Babka
- Removal of dead code from deactivate_slab() by Hyeonggon Yoo. - Fix of BUILD_BUG_ON() for sufficient early percpu size by Baoquan He. - Make kmem_cache_alloc() kernel-doc less misleading, by myself.
2022-11-21slab: Remove special-casing of const 0 size allocationsKees Cook
Passing a constant-0 size allocation into kmalloc() or kmalloc_node() does not need to be a fast-path operation, so the static return value can be removed entirely. This makes sure that all paths through the inlines result in a full extern function call, where __alloc_size() hints will actually be seen[1] by GCC. (A constant return value of 0 means the "0" allocation size won't be propagated by the inline.) [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96503 Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: linux-mm@kvack.org Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2022-11-21slab: Clean up SLOB vs kmalloc() definitionKees Cook
As already done for kmalloc_node(), clean up the #ifdef usage in the definition of kmalloc() so that the SLOB-only version is an entirely separate and much more readable function. Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: linux-mm@kvack.org Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2022-11-21Merge 6.1-rc6 into driver-core-nextGreg Kroah-Hartman
We need the kernfs changes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-21mm/slab: move and adjust kernel-doc for kmem_cache_allocVlastimil Babka
Alexander reports an issue with the kmem_cache_alloc() comment in mm/slab.c: > The current comment mentioned that the flags only matters if the > cache has no available objects. It's different for the __GFP_ZERO > flag which will ensure that the returned object is always zeroed > in any case. > I have the feeling I run into this question already two times if > the user need to zero the object or not, but the user does not need > to zero the object afterwards. However another use of __GFP_ZERO > and only zero the object if the cache has no available objects would > also make no sense. and suggests thus mentioning __GFP_ZERO as the exception. But on closer inspection, the part about flags being only relevant if cache has no available objects is misleading. The slab user has no reliable way to determine if there are available objects, and e.g. the might_sleep() debug check can be performed even if objects are available, so passing correct flags given the allocation context always matters. Thus remove that sentence completely, and while at it, move the comment to from SLAB-specific mm/slab.c to the common include/linux/slab.h The comment otherwise refers flags description for kmalloc(), so add __GFP_ZERO comment there and remove a very misleading GFP_HIGHUSER (not applicable to slab) description from there. Mention kzalloc() and kmem_cache_zalloc() shortcuts. Reported-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/all/20221011145413.8025-1-aahringo@redhat.com/ Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2022-11-21percpu: adjust the value of PERCPU_DYNAMIC_EARLY_SIZEBaoquan He
LKP reported a build failure as below on the following patch "mm/slub, percpu: correct the calculation of early percpu allocation size" ~~~~~~ In file included from <command-line>: In function 'alloc_kmem_cache_cpus', inlined from 'kmem_cache_open' at mm/slub.c:4340:6: >> >> include/linux/compiler_types.h:357:45: error: call to '__compiletime_assert_474' declared with attribute error: BUILD_BUG_ON failed: PERCPU_DYNAMIC_EARLY_SIZE < NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * sizeof(struct kmem_cache_cpu) 357 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ~~~~~~ From the kernel config file provided by LKP, the building was made on arm64 with below Kconfig item enabled: CONFIG_ZONE_DMA=y CONFIG_SLUB_CPU_PARTIAL=y CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_SLUB_STATS=y CONFIG_ARM64_PAGE_SHIFT=16 CONFIG_ARM64_64K_PAGES=y Then we will have: NR_KMALLOC_TYPES:4 KMALLOC_SHIFT_HIGH:17 sizeof(struct kmem_cache_cpu):184 The product of them is 12512, which is bigger than PERCPU_DYNAMIC_EARLY_SIZE, 12K. Hence, the BUILD_BUG_ON in alloc_kmem_cache_cpus() is triggered. Earlier, in commit 099a19d91ca4 ("percpu: allow limited allocation before slab is online"), PERCPU_DYNAMIC_EARLY_SIZE was introduced and set to 12K which is equal to the then PERPCU_DYNAMIC_RESERVE. Later, in commit 1a4d76076cda ("percpu: implement asynchronous chunk population"), PERPCU_DYNAMIC_RESERVE was increased by 8K, while PERCPU_DYNAMIC_EARLY_SIZE was kept unchanged. So, here increase PERCPU_DYNAMIC_EARLY_SIZE by 8K too to accommodate to the slub's requirement. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2022-11-20sched: Move numa_balancing sysctls to its own fileKefeng Wang
The sysctl_numa_balancing_promote_rate_limit and sysctl_numa_balancing are part of sched, move them to its own file. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-11-20bpf: Add a kfunc to type cast from bpf uapi ctx to kernel ctxYonghong Song
Implement bpf_cast_to_kern_ctx() kfunc which does a type cast of a uapi ctx object to the corresponding kernel ctx. Previously if users want to access some data available in kctx but not in uapi ctx, bpf_probe_read_kernel() helper is needed. The introduction of bpf_cast_to_kern_ctx() allows direct memory access which makes code simpler and easier to understand. Signed-off-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20221120195432.3113982-1-yhs@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20Merge tag 'trace-v6.1-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix polling to block on watermark like the reads do, as user space applications get confused when the select says read is available, and then the read blocks - Fix accounting of ring buffer dropped pages as it is what is used to determine if the buffer is empty or not - Fix memory leak in tracing_read_pipe() - Fix struct trace_array warning about being declared in parameters - Fix accounting of ftrace pages used in output at start up. - Fix allocation of dyn_ftrace pages by subtracting one from order instead of diving it by 2 - Static analyzer found a case were a pointer being used outside of a NULL check (rb_head_page_deactivate()) - Fix possible NULL pointer dereference if kstrdup() fails in ftrace_add_mod() - Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event() - Fix bad pointer dereference in register_synth_event() on error path - Remove unused __bad_type_size() method - Fix possible NULL pointer dereference of entry in list 'tr->err_log' - Fix NULL pointer deference race if eprobe is called before the event setup * tag 'trace-v6.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix race where eprobes can be called before the event tracing: Fix potential null-pointer-access of entry in list 'tr->err_log' tracing: Remove unused __bad_type_size() method tracing: Fix wild-memory-access in register_synth_event() tracing: Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event() ftrace: Fix null pointer dereference in ftrace_add_mod() ring_buffer: Do not deactivate non-existant pages ftrace: Optimize the allocation for mcount entries ftrace: Fix the possible incorrect kernel message tracing: Fix warning on variable 'struct trace_array' tracing: Fix memory leak in tracing_read_pipe() ring-buffer: Include dropped pages in counting dirty patches tracing/ring-buffer: Have polling block on watermark
2022-11-20bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncsDavid Vernet
Kfuncs currently support specifying the KF_TRUSTED_ARGS flag to signal to the verifier that it should enforce that a BPF program passes it a "safe", trusted pointer. Currently, "safe" means that the pointer is either PTR_TO_CTX, or is refcounted. There may be cases, however, where the kernel passes a BPF program a safe / trusted pointer to an object that the BPF program wishes to use as a kptr, but because the object does not yet have a ref_obj_id from the perspective of the verifier, the program would be unable to pass it to a KF_ACQUIRE | KF_TRUSTED_ARGS kfunc. The solution is to expand the set of pointers that are considered trusted according to KF_TRUSTED_ARGS, so that programs can invoke kfuncs with these pointers without getting rejected by the verifier. There is already a PTR_UNTRUSTED flag that is set in some scenarios, such as when a BPF program reads a kptr directly from a map without performing a bpf_kptr_xchg() call. These pointers of course can and should be rejected by the verifier. Unfortunately, however, PTR_UNTRUSTED does not cover all the cases for safety that need to be addressed to adequately protect kfuncs. Specifically, pointers obtained by a BPF program "walking" a struct are _not_ considered PTR_UNTRUSTED according to BPF. For example, say that we were to add a kfunc called bpf_task_acquire(), with KF_ACQUIRE | KF_TRUSTED_ARGS, to acquire a struct task_struct *. If we only used PTR_UNTRUSTED to signal that a task was unsafe to pass to a kfunc, the verifier would mistakenly allow the following unsafe BPF program to be loaded: SEC("tp_btf/task_newtask") int BPF_PROG(unsafe_acquire_task, struct task_struct *task, u64 clone_flags) { struct task_struct *acquired, *nested; nested = task->last_wakee; /* Would not be rejected by the verifier. */ acquired = bpf_task_acquire(nested); if (!acquired) return 0; bpf_task_release(acquired); return 0; } To address this, this patch defines a new type flag called PTR_TRUSTED which tracks whether a PTR_TO_BTF_ID pointer is safe to pass to a KF_TRUSTED_ARGS kfunc or a BPF helper function. PTR_TRUSTED pointers are passed directly from the kernel as a tracepoint or struct_ops callback argument. Any nested pointer that is obtained from walking a PTR_TRUSTED pointer is no longer PTR_TRUSTED. From the example above, the struct task_struct *task argument is PTR_TRUSTED, but the 'nested' pointer obtained from 'task->last_wakee' is not PTR_TRUSTED. A subsequent patch will add kfuncs for storing a task kfunc as a kptr, and then another patch will add selftests to validate. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20221120051004.3605026-3-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20bpf: Allow multiple modifiers in reg_type_str() prefixDavid Vernet
reg_type_str() in the verifier currently only allows a single register type modifier to be present in the 'prefix' string which is eventually stored in the env type_str_buf. This currently works fine because there are no overlapping type modifiers, but once PTR_TRUSTED is added, that will no longer be the case. This patch updates reg_type_str() to support having multiple modifiers in the prefix string, and updates the size of type_str_buf to be 128 bytes. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20221120051004.3605026-2-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20PM/devfreq: governor: Add a private governor_data for governorKant Fan
The member void *data in the structure devfreq can be overwrite by governor_userspace. For example: 1. The device driver assigned the devfreq governor to simple_ondemand by the function devfreq_add_device() and init the devfreq member void *data to a pointer of a static structure devfreq_simple_ondemand_data by the function devfreq_add_device(). 2. The user changed the devfreq governor to userspace by the command "echo userspace > /sys/class/devfreq/.../governor". 3. The governor userspace alloced a dynamic memory for the struct userspace_data and assigend the member void *data of devfreq to this memory by the function userspace_init(). 4. The user changed the devfreq governor back to simple_ondemand by the command "echo simple_ondemand > /sys/class/devfreq/.../governor". 5. The governor userspace exited and assigned the member void *data in the structure devfreq to NULL by the function userspace_exit(). 6. The governor simple_ondemand fetched the static information of devfreq_simple_ondemand_data in the function devfreq_simple_ondemand_func() but the member void *data of devfreq was assigned to NULL by the function userspace_exit(). 7. The information of upthreshold and downdifferential is lost and the governor simple_ondemand can't work correctly. The member void *data in the structure devfreq is designed for a static pointer used in a governor and inited by the function devfreq_add_device(). This patch add an element named governor_data in the devfreq structure which can be used by a governor(E.g userspace) who want to assign a private data to do some private things. Fixes: ce26c5bb9569 ("PM / devfreq: Add basic governors") Cc: stable@vger.kernel.org # 5.10+ Reviewed-by: Chanwoo Choi <cwchoi00@gmail.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kant Fan <kant@allwinnertech.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2022-11-19watchdog: rn5t618: add support for read out bootstatusMarcus Folkesson
The PMIC does store the power-off factor internally. Read it out and report it as bootstatus. Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> Acked-by: Lee Jones <lee@kernel.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20221028075019.2757812-1-marcus.folkesson@gmail.com Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-11-19iommu/io-pgtable: Remove map/unmapRobin Murphy
With all users now calling {map,unmap}_pages, retire the redundant single-page callbacks. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/a5a3cbf95c3279982e378cc43dad830322a59868.1668100209.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2022-11-18Merge tag 'io_uring-6.1-2022-11-18' of git://git.kernel.dk/linuxLinus Torvalds
Pull io_uring fixes from Jens Axboe: "This is mostly fixing issues around the poll rework, but also two tweaks for the multishot handling for accept and receive. All stable material" * tag 'io_uring-6.1-2022-11-18' of git://git.kernel.dk/linux: io_uring: disallow self-propelled ring polling io_uring: fix multishot recv request leaks io_uring: fix multishot accept request leaks io_uring: fix tw losing poll events io_uring: update res mask in io_poll_check_events
2022-11-18lsm,fs: fix vfs_getxattr_alloc() return type and caller error pathsPaul Moore
The vfs_getxattr_alloc() function currently returns a ssize_t value despite the fact that it only uses int values internally for return values. Fix this by converting vfs_getxattr_alloc() to return an int type and adjust the callers as necessary. As part of these caller modifications, some of the callers are fixed to properly free the xattr value buffer on both success and failure to ensure that memory is not leaked in the failure case. Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-11-18Merge tag 'block-6.1-2022-11-18' of git://git.kernel.dk/linuxLinus Torvalds
Pull block fixes from Jens Axboe: - NVMe pull request via Christoph: - Two more bogus nid quirks (Bean Huo, Tiago Dias Ferreira) - Memory leak fix in nvmet (Sagi Grimberg) - Regression fix for block cgroups pinning the wrong blkcg, causing leaks of cgroups and blkcgs (Chris) - UAF fix for drbd setup error handling (Dan) - Fix DMA alignment propagation in DM (Keith) * tag 'block-6.1-2022-11-18' of git://git.kernel.dk/linux: dm-log-writes: set dma_alignment limit in io_hints dm-integrity: set dma_alignment limit in io_hints block: make blk_set_default_limits() private dm-crypt: provide dma_alignment limit in io_hints block: make dma_alignment a stacking queue_limit nvmet: fix a memory leak in nvmet_auth_set_key nvme-pci: add NVME_QUIRK_BOGUS_NID for Netac NV7000 drbd: use after free in drbd_create_device() nvme-pci: add NVME_QUIRK_BOGUS_NID for Micron Nitro blk-cgroup: properly pin the parent in blkcg_css_online
2022-11-18proc: give /proc/cmdline sizeAlexey Dobriyan
Most /proc files don't have length (in fstat sense). This leads to inefficiencies when reading such files with APIs commonly found in modern programming languages. They open file, then fstat descriptor, get st_size == 0 and either assume file is empty or start reading without knowing target size. cat(1) does OK because it uses large enough buffer by default. But naive programs copy-pasted from SO aren't: let mut f = std::fs::File::open("/proc/cmdline").unwrap(); let mut buf: Vec<u8> = Vec::new(); f.read_to_end(&mut buf).unwrap(); will result in openat(AT_FDCWD, "/proc/cmdline", O_RDONLY|O_CLOEXEC) = 3 statx(0, NULL, AT_STATX_SYNC_AS_STAT, STATX_ALL, NULL) = -1 EFAULT (Bad address) statx(3, "", AT_STATX_SYNC_AS_STAT|AT_EMPTY_PATH, STATX_ALL, {stx_mask=STATX_BASIC_STATS|STATX_MNT_ID, stx_attributes=0, stx_mode=S_IFREG|0444, stx_size=0, ...}) = 0 lseek(3, 0, SEEK_CUR) = 0 read(3, "BOOT_IMAGE=(hd3,gpt2)/vmlinuz-5.", 32) = 32 read(3, "19.6-100.fc35.x86_64 root=/dev/m", 32) = 32 read(3, "apper/fedora_localhost--live-roo"..., 64) = 64 read(3, "ocalhost--live-swap rd.lvm.lv=fe"..., 128) = 116 read(3, "", 12) open/stat is OK, lseek looks silly but there are 3 unnecessary reads because Rust starts with 32 bytes per Vec<u8> and grows from there. In case of /proc/cmdline, the length is known precisely. Make variables readonly while I'm at it. P.S.: I tried to scp /proc/cpuinfo today and got empty file but this is separate story. Link: https://lkml.kernel.org/r/YxoywlbM73JJN3r+@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-18minmax: clamp more efficiently by avoiding extra comparisonJason A. Donenfeld
Currently the clamp algorithm does: if (val > hi) val = hi; if (val < lo) val = lo; But since hi > lo by definition, this can be made more efficient with: if (val > hi) val = hi; else if (val < lo) val = lo; So fix up the clamp and clamp_t functions to do this, adding the same argument checking as for min and min_t. For simple cases, code generation on x86_64 and aarch64 stay about the same: before: cmp edi, edx mov eax, esi cmova edi, edx cmp edi, esi cmovnb eax, edi ret after: cmp edi, esi mov eax, edx cmovnb esi, edi cmp edi, edx cmovb eax, esi ret before: cmp w0, w2 csel w8, w0, w2, lo cmp w8, w1 csel w0, w8, w1, hi ret after: cmp w0, w1 csel w8, w0, w1, hi cmp w0, w2 csel w0, w8, w2, lo ret On MIPS64, however, code generation improves, by removing arithmetic in the second branch: before: sltu $3,$6,$4 bne $3,$0,.L2 move $2,$6 move $2,$4 .L2: sltu $3,$2,$5 bnel $3,$0,.L7 move $2,$5 .L7: jr $31 nop after: sltu $3,$4,$6 beq $3,$0,.L13 move $2,$6 sltu $3,$4,$5 bne $3,$0,.L12 move $2,$4 .L13: jr $31 nop .L12: jr $31 move $2,$5 For more complex cases with surrounding code, the effects are a bit more complicated. For example, consider this simplified version of timestamp_truncate() from fs/inode.c on x86_64: struct timespec64 timestamp_truncate(struct timespec64 t, struct inode *inode) { struct super_block *sb = inode->i_sb; unsigned int gran = sb->s_time_gran; t.tv_sec = clamp(t.tv_sec, sb->s_time_min, sb->s_time_max); if (t.tv_sec == sb->s_time_max || t.tv_sec == sb->s_time_min) t.tv_nsec = 0; return t; } before: mov r8, rdx mov rdx, rsi mov rcx, QWORD PTR [r8] mov rax, QWORD PTR [rcx+8] mov rcx, QWORD PTR [rcx+16] cmp rax, rdi mov r8, rcx cmovge rdi, rax cmp rdi, rcx cmovle r8, rdi cmp rax, r8 je .L4 cmp rdi, rcx jge .L4 mov rax, r8 ret .L4: xor edx, edx mov rax, r8 ret after: mov rax, QWORD PTR [rdx] mov rdx, QWORD PTR [rax+8] mov rax, QWORD PTR [rax+16] cmp rax, rdi jg .L6 mov r8, rax xor edx, edx .L2: mov rax, r8 ret .L6: cmp rdx, rdi mov r8, rdi cmovge r8, rdx cmp rax, r8 je .L4 xor eax, eax cmp rdx, rdi cmovl rax, rsi mov rdx, rax mov rax, r8 ret .L4: xor edx, edx jmp .L2 In this case, we actually gain a branch, unfortunately, because the compiler's replacement axioms no longer as cleanly apply. So all and all, this change is a bit of a mixed bag. Link: https://lkml.kernel.org/r/20220926133435.1333846-2-Jason@zx2c4.com Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-18minmax: sanity check constant bounds when clampingJason A. Donenfeld
The clamp family of functions only makes sense if hi>=lo. If hi and lo are compile-time constants, then raise a build error. Doing so has already caught buggy code. This also introduces the infrastructure to improve the clamping function in subsequent commits. [akpm@linux-foundation.org: coding-style cleanups] [akpm@linux-foundation.org: s@&&\@&& \@] Link: https://lkml.kernel.org/r/20220926133435.1333846-1-Jason@zx2c4.com Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-18kexec: replace crash_mem_range with rangeLi Chen
We already have struct range, so just use it. Link: https://lkml.kernel.org/r/20220929042936.22012-4-bhe@redhat.com Signed-off-by: Li Chen <lchen@ambarella.com> Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Chen Lifu <chenlifu@huawei.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Jianglei Nie <niejianglei2021@163.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Russell King <linux@armlinux.org.uk> Cc: ye xingchen <ye.xingchen@zte.com.cn> Cc: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-18core_pattern: add CPU specifierOleksandr Natalenko
Statistically, in a large deployment regular segfaults may indicate a CPU issue. Currently, it is not possible to find out what CPU the segfault happened on. There are at least two attempts to improve segfault logging with this regard, but they do not help in case the logs rotate. Hence, lets make sure it is possible to permanently record a CPU the task ran on using a new core_pattern specifier. Link: https://lkml.kernel.org/r/20220903064330.20772-1-oleksandr@redhat.com Signed-off-by: Oleksandr Natalenko <oleksandr@redhat.com> Suggested-by: Renaud Métrich <rmetrich@redhat.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Grzegorz Halat <ghalat@redhat.com> Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Joel Savitz <jsavitz@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <keescook@chromium.org> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Stephen Kitt <steve@sk2.org> Cc: Will Deacon <will@kernel.org> Cc: Xiaoming Ni <nixiaoming@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-18driver core: Add __alloc_size hint to devm allocatorsKees Cook
Mark the devm_*alloc()-family of allocations with appropriate __alloc_size()/__realloc_size() hints so the compiler can attempt to reason about buffer lengths from allocations. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Nishanth Menon <nm@ti.com> Cc: Michael Kelley <mikelley@microsoft.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Won Chung <wonchung@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20221029074734.gonna.276-kees@kernel.org
2022-11-18KVM: x86: avoid memslot check in NX hugepage recovery if it cannot succeedPaolo Bonzini
Since gfn_to_memslot() is relatively expensive, it helps to skip it if it the memslot cannot possibly have dirty logging enabled. In order to do this, add to struct kvm a counter of the number of log-page memslots. While the correct value can only be read with slots_lock taken, the NX recovery thread is content with using an approximate value. Therefore, the counter is an atomic_t. Based on https://lore.kernel.org/kvm/20221027200316.2221027-2-dmatlack@google.com/ by David Matlack. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18regulator: Add of_regulator_bulk_get_all()Mark Brown
Merge series from Corentin Labbe <clabbe@baylibre.com>: This adds a new regulator_bulk_get_all() which grab all supplies properties in a DT node, for use in implementing generic handling for things like MDIO PHYs where the physical standardisation of the bus does not extend to power supplies.
2022-11-18regulator: Add of_regulator_bulk_get_allCorentin Labbe
It work exactly like regulator_bulk_get() but instead of working on a provided list of names, it seek all consumers properties matching xxx-supply. Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Link: https://lore.kernel.org/r/20221115073603.3425396-2-clabbe@baylibre.com Signed-off-by: Mark Brown <broonie@kernel.org>
2022-11-18ftrace: abstract DYNAMIC_FTRACE_WITH_ARGS accessesMark Rutland
In subsequent patches we'll arrange for architectures to have an ftrace_regs which is entirely distinct from pt_regs. In preparation for this, we need to minimize the use of pt_regs to where strictly necessary in the core ftrace code. This patch adds new ftrace_regs_{get,set}_*() helpers which can be used to manipulate ftrace_regs. When CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=y, these can always be used on any ftrace_regs, and when CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=n these can be used when regs are available. A new ftrace_regs_has_args(fregs) helper is added which code can use to check when these are usable. Co-developed-by: Florent Revest <revest@chromium.org> Signed-off-by: Florent Revest <revest@chromium.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20221103170520.931305-4-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-18ftrace: rename ftrace_instruction_pointer_set() -> ↵Mark Rutland
ftrace_regs_set_instruction_pointer() In subsequent patches we'll add a sew of ftrace_regs_{get,set}_*() helpers. In preparation, this patch renames ftrace_instruction_pointer_set() to ftrace_regs_set_instruction_pointer(). There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20221103170520.931305-3-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-18ftrace: pass fregs to arch_ftrace_set_direct_caller()Mark Rutland
In subsequent patches we'll arrange for architectures to have an ftrace_regs which is entirely distinct from pt_regs. In preparation for this, we need to minimize the use of pt_regs to where strictly necessary in the core ftrace code. This patch changes the prototype of arch_ftrace_set_direct_caller() to take ftrace_regs rather than pt_regs, and moves the extraction of the pt_regs into arch_ftrace_set_direct_caller(). On x86, arch_ftrace_set_direct_caller() can be used even when CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=n, and <linux/ftrace.h> defines struct ftrace_regs. Due to this, it's necessary to define arch_ftrace_set_direct_caller() as a macro to avoid using an incomplete type. I've also moved the body of arch_ftrace_set_direct_caller() after the CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=y defineidion of struct ftrace_regs. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20221103170520.931305-2-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-18Merge tag 'wireless-next-2022-11-18' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next Kalle Valo says: ==================== wireless-next patches for v6.2 Second set of patches for v6.2. Only driver patches this time, nothing really special. Unused platform data support was removed from wl1251 and rtw89 got WoWLAN support. Major changes: ath11k * support configuring channel dwell time during scan rtw89 * new dynamic header firmware format support * Wake-over-WLAN support rtl8xxxu * enable IEEE80211_HW_SUPPORT_FAST_XMIT ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-18mmc: core: Fix ambiguous TRIM and DISCARD argChristian Löhle
Clean up the MMC_TRIM_ARGS define that became ambiguous with DISCARD introduction. While at it, let's fix one usage where MMC_TRIM_ARGS falsely included DISCARD too. Fixes: b3bf915308ca ("mmc: core: new discard feature support at eMMC v4.5") Signed-off-by: Christian Loehle <cloehle@hyperstone.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/11376b5714964345908f3990f17e0701@hyperstone.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2022-11-18efi: random: combine bootloader provided RNG seed with RNG protocol outputArd Biesheuvel
Instead of blindly creating the EFI random seed configuration table if the RNG protocol is implemented and works, check whether such a EFI configuration table was provided by an earlier boot stage and if so, concatenate the existing and the new seeds, leaving it up to the core code to mix it in and credit it the way it sees fit. This can be used for, e.g., systemd-boot, to pass an additional seed to Linux in a way that can be consumed by the kernel very early. In that case, the following definitions should be used to pass the seed to the EFI stub: struct linux_efi_random_seed { u32 size; // of the 'seed' array in bytes u8 seed[]; }; The memory for the struct must be allocated as EFI_ACPI_RECLAIM_MEMORY pool memory, and the address of the struct in memory should be installed as a EFI configuration table using the following GUID: LINUX_EFI_RANDOM_SEED_TABLE_GUID 1ce1e5bc-7ceb-42f2-81e5-8aadf180f57b Note that doing so is safe even on kernels that were built without this patch applied, but the seed will simply be overwritten with a seed derived from the EFI RNG protocol, if available. The recommended seed size is 32 bytes, and seeds larger than 512 bytes are considered corrupted and ignored entirely. In order to preserve forward secrecy, seeds from previous bootloaders are memzero'd out, and in order to preserve memory, those older seeds are also freed from memory. Freeing from memory without first memzeroing is not safe to do, as it's possible that nothing else will ever overwrite those pages used by EFI. Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com> [ardb: incorporate Jason's followup changes to extend the maximum seed size on the consumer end, memzero() it and drop a needless printk] Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-18crypto: hisilicon/qm - modify the process of regs dfxKai Ye
The last register logic and different register logic are combined. Use "u32" instead of 'int' in the regs function input parameter to simplify some checks. Signed-off-by: Kai Ye <yekai13@huawei.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-11-18crypto: hisilicon/qm - add missing pci_dev_put() in q_num_set()Xiongfeng Wang
pci_get_device() will increase the reference count for the returned pci_dev. We need to use pci_dev_put() to decrease the reference count before q_num_set() returns. Fixes: c8b4b477079d ("crypto: hisilicon - add HiSilicon HPRE accelerator") Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Reviewed-by: Weili Qian <qianweili@huawei.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-11-18hwrng: core - treat default_quality as a maximum and default to 1024Jason A. Donenfeld
Most hw_random devices return entropy which is assumed to be of full quality, but driver authors don't bother setting the quality knob. Some hw_random devices return less than full quality entropy, and then driver authors set the quality knob. Therefore, the entropy crediting should be opt-out rather than opt-in per-driver, to reflect the actual reality on the ground. For example, the two Raspberry Pi RNG drivers produce full entropy randomness, and both EDK2 and U-Boot's drivers for these treat them as such. The result is that EFI then uses these numbers and passes the to Linux, and Linux credits them as boot, thereby initializing the RNG. Yet, in Linux, the quality knob was never set to anything, and so on the chance that Linux is booted without EFI, nothing is ever credited. That's annoying. The same pattern appears to repeat itself throughout various drivers. In fact, very very few drivers have bothered setting quality=1024. Looking at the git history of existing drivers and corresponding mailing list discussion, this conclusion tracks. There's been a decent amount of discussion about drivers that set quality < 1024 -- somebody read and interepreted a datasheet, or made some back of the envelope calculation somehow. But there's been very little, if any, discussion about most drivers where the quality is just set to 1024 or unset (or set to 1000 when the authors misunderstood the API and assumed it was base-10 rather than base-2); in both cases the intent was fairly clear of, "this is a hardware random device; it's fine." So let's invert this logic. A hw_random struct's quality knob now controls the maximum quality a driver can produce, or 0 to specify 1024. Then, the module-wide switch called "default_quality" is changed to represent the maximum quality of any driver. By default it's 1024, and the quality of any particular driver is then given by: min(default_quality, rng->quality ?: 1024); This way, the user can still turn this off for weird reasons (and we can replace whatever driver-specific disabling hacks existed in the past), yet we get proper crediting for relevant RNGs. Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-11-18Merge tag 'intel-pinctrl-v6.2-1' of ↵Linus Walleij
git://git.kernel.org/pub/scm/linux/kernel/git/pinctrl/intel into devel intel-pinctrl for v6.2-1 * Add Intel Moorefield pin control driver * Deduplicate COMMUNITY() macro in the Intel pin control drivers * Switch Freescale GPIO driver to use fwnode instead of of_node * Miscellaneous clenups here and there The following is an automated git shortlog grouped by driver: alderlake: - Deduplicate COMMUNITY macro code cannonlake: - Deduplicate COMMUNITY macro code device property: - Introduce fwnode_device_is_compatible() helper icelake: - Deduplicate COMMUNITY macro code intel: - Add Intel Moorefield pin controller support - Use temporary variable for struct device - Use str_enable_disable() helper merrifield: - Use temporary variable for struct device qcom: - lpass-lpi: Add missed bitfield.h soc: - fsl: qe: Switch to use fwnode instead of of_node sunrisepoint: - Deduplicate COMMUNITY macro code tigerlake: - Deduplicate COMMUNITY macro code
2022-11-18efi/cper, cxl: Decode CXL Error LogSmita Koralahalli
Print the CXL Error Log field as found in CXL Protocol Error Section. The CXL RAS Capability structure will be reused by OS First Handling and the duplication/appropriate placement will be addressed eventually. Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-18efi: x86: Move EFI runtime map sysfs code to arch/x86Ard Biesheuvel
The EFI runtime map code is only wired up on x86, which is the only architecture that has a need for it in its implementation of kexec. So let's move this code under arch/x86 and drop all references to it from generic code. To ensure that the efi_runtime_map_init() is invoked at the appropriate time use a 'sync' subsys_initcall() that will be called right after the EFI initcall made from generic code where the original invocation of efi_runtime_map_init() resided. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Dave Young <dyoung@redhat.com>
2022-11-18efi: memmap: Move manipulation routines into x86 arch treeArd Biesheuvel
The EFI memory map is a description of the memory layout as provided by the firmware, and only x86 manipulates it in various different ways for its own memory bookkeeping. So let's move the memmap routines that are only used by x86 into the x86 arch tree. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-18efi: memmap: Move EFI fake memmap support into x86 arch treeArd Biesheuvel
The EFI fake memmap support is specific to x86, which manipulates the EFI memory map in various different ways after receiving it from the EFI stub. On other architectures, we have managed to push back on this, and the EFI memory map is kept pristine. So let's move the fake memmap code into the x86 arch tree, where it arguably belongs. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-18efi: libstub: Implement devicepath support for initrd commandline loaderArd Biesheuvel
Currently, the initrd= command line option to the EFI stub only supports loading files that reside on the same volume as the loaded image, which is not workable for loaders like GRUB that don't even implement the volume abstraction (EFI_SIMPLE_FILE_SYSTEM_PROTOCOL), and load the kernel from an anonymous buffer in memory. For this reason, another method was devised that relies on the LoadFile2 protocol. However, the command line loader is rather useful when using the UEFI shell or other generic loaders that have no awareness of Linux specific protocols so let's make it a bit more flexible, by permitting textual device paths to be provided to initrd= as well, provided that they refer to a file hosted on a EFI_SIMPLE_FILE_SYSTEM_PROTOCOL volume. E.g., initrd=PciRoot(0x0)/Pci(0x3,0x0)/HD(1,MBR,0xBE1AFDFA,0x3F,0xFBFC1)/rootfs.cpio.gz Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-18Merge tag 'efi-zboot-direct-for-v6.2' into efi/nextArd Biesheuvel
2022-11-17Input: max8997 - convert to modern way to get a reference to a PWMUwe Kleine-König
pwm_request() isn't recommended to be used any more because it relies on global IDs for the PWM which comes with different difficulties. The new way to do things is to find the right PWM using a reference from the platform device. (This can be created either using a device-tree or a platform lookup table, see e.g. commit 5a4412d4a82f ("ARM: pxa: tavorevb: Use PWM lookup table") how to do this.) There are no in-tree users, so there are no other code locations that need adaption. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Lee Jones <lee@kernel.org> Link: https://lore.kernel.org/r/20221117073543.3790449-1-u.kleine-koenig@pengutronix.de Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2022-11-17sctp: move SCTP_PAD4 and SCTP_TRUNC4 to linux/sctp.hXin Long
Move these two macros from net/sctp/sctp.h to linux/sctp.h, so that it will be enough to include only linux/sctp.h in nft_exthdr.c and xt_sctp.c. It should not include "net/sctp/sctp.h" if a module does not have a dependence on SCTP module. Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Saeed Mahameed <saeed@kernel.org> Link: https://lore.kernel.org/r/ef6468a687f36da06f575c2131cd4612f6b7be88.1668526821.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17ethtool: doc: clarify what drivers can implement in their get_drvinfo()Vincent Mailhol
Many of the drivers which implement ethtool_ops::get_drvinfo() will prints the .driver, .version or .bus_info of struct ethtool_drvinfo. To have a glance of current state, do: $ git grep -W "get_drvinfo(struct" Printing in those three fields is useless because: - since [1], the driver version should be the kernel version (at least for upstream drivers). Arguably, out of tree drivers might still want to set a custom version, but out of tree is not our focus. - since [2], the core is able to provide default values for .driver and .bus_info. In summary, drivers may provide .fw_version and .erom_version, the rest is expected to be done by the core. In struct ethtool_ops doc from linux/ethtool: rephrase field get_drvinfo() doc to discourage developers from implementing this callback. In struct ethtool_drvinfo doc from uapi/linux/ethtool.h: remove the paragraph mentioning what drivers should do. Rationale: no need to repeat what is already written in struct ethtool_ops doc. But add a note that .fw_version and .erom_version are driver defined. Also update the dummy driver and simply remove the callback in order not to confuse the newcomers: most of the drivers will not need this callback function any more. [1] commit 6a7e25c7fb48 ("net/core: Replace driver version to be kernel version") Link: https://git.kernel.org/torvalds/linux/c/6a7e25c7fb48 [2] commit edaf5df22cb8 ("ethtool: ethtool_get_drvinfo: populate drvinfo fields even if callback exits") Link: https://git.kernel.org/netdev/net-next/c/edaf5df22cb8 Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20221116171828.4093-1-mailhol.vincent@wanadoo.fr Signed-off-by: Jakub Kicinski <kuba@kernel.org>