summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/alternative.c
AgeCommit message (Collapse)Author
2025-04-11x86/alternatives: Rename 'text_poke_loc_init()' to 'text_poke_int3_loc_init()'Ingo Molnar
This name is actively confusing as well, because the simple text_poke*() APIs use MM-switching based code patching, while text_poke_loc_init() is part of the INT3 based text_poke_int3_*() machinery that is an additional layer of functionality on top of regular text_poke*() functionality. Rename it to text_poke_int3_loc_init() to make it clear which layer it belongs to. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-18-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'text_poke_queue()' to 'smp_text_poke_batch_add()'Ingo Molnar
This name is actively confusing as well, because the simple text_poke*() APIs use MM-switching based code patching, while text_poke_queue() is part of the INT3 based text_poke_int3_*() machinery that is an additional layer of functionality on top of regular text_poke*() functionality. Rename it to smp_text_poke_batch_add() to make it clear which layer it belongs to. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-17-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'text_poke_finish()' to 'smp_text_poke_batch_finish()'Ingo Molnar
This name is actively confusing as well, because the simple text_poke*() APIs use MM-switching based code patching, while text_poke_finish() is part of the INT3 based text_poke_int3_*() machinery that is an additional layer of functionality on top of regular text_poke*() functionality. Rename it to smp_text_poke_batch_finish() to make it clear which layer it belongs to. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-16-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'text_poke_flush()' to 'smp_text_poke_batch_flush()'Ingo Molnar
This name is actually actively confusing, because the simple text_poke*() APIs use MM-switching based code patching, while text_poke_flush() is part of the INT3 based text_poke_int3_*() machinery that is an additional layer of functionality on top of regular text_poke*() functionality. Rename it to smp_text_poke_batch_flush() to make it clear which layer it belongs to. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-15-mingo@kernel.org
2025-04-11x86/alternatives: Remove the confusing, inaccurate & unnecessary ↵Ingo Molnar
'temp_mm_state_t' abstraction So the temp_mm_state_t abstraction used by use_temporary_mm() and unuse_temporary_mm() is super confusing: - The whole machinery is about temporarily switching to the text_poke_mm utility MM that got allocated during bootup for text-patching purposes alone: temp_mm_state_t prev; /* * Loading the temporary mm behaves as a compiler barrier, which * guarantees that the PTE will be set at the time memcpy() is done. */ prev = use_temporary_mm(text_poke_mm); - Yet the value that gets saved in the temp_mm_state_t variable is not the temporary MM ... but the previous MM... - Ie. we temporarily put the non-temporary MM into a variable that has the temp_mm_state_t type. This makes no sense whatsoever. - The confusion continues in unuse_temporary_mm(): static inline void unuse_temporary_mm(temp_mm_state_t prev_state) Here we unuse an MM that is ... not the temporary MM, but the previous MM. :-/ Fix up all this confusion by removing the unnecessary layer of abstraction and using a bog-standard 'struct mm_struct *prev_mm' variable to save the MM to. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-14-mingo@kernel.org
2025-04-11x86/alternatives: Remove duplicate 'text_poke_early()' prototypeIngo Molnar
It's declared in <asm/text-patching.h> already. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-12-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'bp_desc' to 'int3_desc'Ingo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-11-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'poking_addr' to 'text_poke_mm_addr'Ingo Molnar
Put it into the text_poke_* namespace of <asm/text-patching.h>. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-10-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'poking_mm' to 'text_poke_mm'Ingo Molnar
Put it into the text_poke_* namespace of <asm/text-patching.h>. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-9-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'poke_int3_handler()' to 'smp_text_poke_int3_handler()'Ingo Molnar
All related functions in this subsystem already have a text_poke_int3_ prefix - add it to the trap handler as well. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-8-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'text_poke_bp()' to 'smp_text_poke_single()'Ingo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-7-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'text_poke_bp_batch()' to ↵Ingo Molnar
'smp_text_poke_batch_process()' Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-6-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'bp_refs' to 'text_poke_array_refs'Ingo Molnar
Make it clear that these reference counts lock access to text_poke_array. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-5-mingo@kernel.org
2025-04-11x86/alternatives: Rename 'struct bp_patching_desc' to 'struct ↵Ingo Molnar
text_poke_int3_vec' Follow the INT3 text-poking nomenclature, and also adopt the 'vector' name for the entire object, instead of the rather opaque 'descriptor' naming. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250411054105.2341982-4-mingo@kernel.org
2025-04-11x86/alternatives: Document the text_poke_bp_batch() synchronization rules a ↵Peter Zijlstra
bit more Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20250411054105.2341982-3-mingo@kernel.org
2025-04-11x86/alternatives: Improve code-patching scalability by removing false ↵Eric Dumazet
sharing in poke_int3_handler() eBPF programs can be run 50,000,000 times per second on busy servers. Whenever /proc/sys/kernel/bpf_stats_enabled is turned off, hundreds of calls sites are patched from text_poke_bp_batch() and we see a huge loss of performance due to false sharing on bp_desc.refs lasting up to three seconds. 51.30% server_bin [kernel.kallsyms] [k] poke_int3_handler | |--46.45%--poke_int3_handler | exc_int3 | asm_exc_int3 | | | |--24.26%--cls_bpf_classify | | tcf_classify | | __dev_queue_xmit | | ip6_finish_output2 | | ip6_output | | ip6_xmit | | inet6_csk_xmit | | __tcp_transmit_skb Fix this by replacing bp_desc.refs with a per-cpu bp_refs. Before the patch, on a host with 240 cores (480 threads): $ sysctl -wq kernel.bpf_stats_enabled=0 text_poke_bp_batch(nr_entries=164) : Took 2655300 usec $ bpftool prog | grep run_time_ns ... 105: sched_cls name hn_egress tag 699fc5eea64144e3 gpl run_time_ns 3009063719 run_cnt 82757845 : average cost is 36 nsec per call After this patch: $ sysctl -wq kernel.bpf_stats_enabled=0 text_poke_bp_batch(nr_entries=164) : Took 702 usec $ bpftool prog | grep run_time_ns ... 105: sched_cls name hn_egress tag 699fc5eea64144e3 gpl run_time_ns 1928223019 run_cnt 67682728 : average cost is 28 nsec per call Ie. text-patching performance improved 3700x: from 2.65 seconds to 0.0007 seconds. Since the atomic_cond_read_acquire(refs, !VAL) spin-loop was not triggered even once in my tests, add an unlikely() annotation, because this appears to be the common case. [ mingo: Improved the changelog some more. ] Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20250411054105.2341982-2-mingo@kernel.org
2025-03-03x86/ibt: Make cfi_bhi a constant for FINEIBT_BHI=nPeter Zijlstra
Robot yielded a .config that tripped: vmlinux.o: warning: objtool: do_jit+0x276: relocation to !ENDBR: .noinstr.text+0x6a60 This is the result of using __bhi_args[1] in unreachable code; make sure the compiler is able to determine this is unreachable and trigger DCE. Closes: https://lore.kernel.org/oe-kbuild-all/202503030704.H9KFysNS-lkp@intel.com/ Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250303094911.GL5880@noisy.programming.kicks-ass.net
2025-02-26x86/ibt: Optimize the fineibt-bhi arity 1 casePeter Zijlstra
Saves a CALL to an out-of-line thunk for the common case of 1 argument. Suggested-by: Scott Constable <scott.d.constable@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124200.927885784@infradead.org
2025-02-26x86/ibt: Implement FineIBT-BHI mitigationPeter Zijlstra
While WAIT_FOR_ENDBR is specified to be a full speculation stop; it has been shown that some implementations are 'leaky' to such an extend that speculation can escape even the FineIBT preamble. To deal with this, add additional hardening to the FineIBT preamble. Notably, using a new LLVM feature: https://github.com/llvm/llvm-project/commit/e223485c9b38a5579991b8cebb6a200153eee245 which encodes the number of arguments in the kCFI preamble's register. Using this register<->arity mapping, have the FineIBT preamble CALL into a stub clobbering the relevant argument registers in the speculative case. Scott sayeth thusly: Microarchitectural attacks such as Branch History Injection (BHI) and Intra-mode Branch Target Injection (IMBTI) [1] can cause an indirect call to mispredict to an adversary-influenced target within the same hardware domain (e.g., within the kernel). Instructions at the mispredicted target may execute speculatively and potentially expose kernel data (e.g., to a user-mode adversary) through a microarchitectural covert channel such as CPU cache state. CET-IBT [2] is a coarse-grained control-flow integrity (CFI) ISA extension that enforces that each indirect call (or indirect jump) must land on an ENDBR (end branch) instruction, even speculatively*. FineIBT is a software technique that refines CET-IBT by associating each function type with a 32-bit hash and enforcing (at the callee) that the hash of the caller's function pointer type matches the hash of the callee's function type. However, recent research [3] has demonstrated that the conditional branch that enforces FineIBT's hash check can be coerced to mispredict, potentially allowing an adversary to speculatively bypass the hash check: __cfi_foo: ENDBR64 SUB R10d, 0x01234567 JZ foo # Even if the hash check fails and ZF=0, this branch could still mispredict as taken UD2 foo: ... The techniques demonstrated in [3] require the attacker to be able to control the contents of at least one live register at the mispredicted target. Therefore, this patch set introduces a sequence of CMOV instructions at each indirect-callable target that poisons every live register with data that the attacker cannot control whenever the FineIBT hash check fails, thus mitigating any potential attack. The security provided by this scheme has been discussed in detail on an earlier thread [4]. [1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html [2] Intel Software Developer's Manual, Volume 1, Chapter 18 [3] https://www.vusec.net/projects/native-bhi/ [4] https://lore.kernel.org/lkml/20240927194925.707462984@infradead.org/ *There are some caveats for certain processors, see [1] for more info Suggested-by: Scott Constable <scott.d.constable@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124200.820402212@infradead.org
2025-02-26x86/ibt: Add paranoid FineIBT modePeter Zijlstra
Due to concerns about circumvention attacks against FineIBT on 'naked' ENDBR, add an additional caller side hash check to FineIBT. This should make it impossible to pivot over such a 'naked' ENDBR instruction at the cost of an additional load. The specific pivot reported was against the SYSCALL entry site and FRED will have all those holes fixed up. https://lore.kernel.org/linux-hardening/Z60NwR4w%2F28Z7XUa@ubun/ This specific fineibt_paranoid_start[] sequence was concocted by Scott. Suggested-by: Scott Constable <scott.d.constable@intel.com> Reported-by: Jennifer Miller <jmill@asu.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124200.598033084@infradead.org
2025-02-26x86/ibt: Optimize the FineIBT instruction sequencePeter Zijlstra
Scott notes that non-taken branches are faster. Abuse overlapping code that traps instead of explicit UD2 instructions. And LEA does not modify flags and will have less dependencies. Suggested-by: Scott Constable <scott.d.constable@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124200.371942555@infradead.org
2025-02-26x86/alternatives: Clean up preprocessor conditional block commentsIngo Molnar
When in the middle of a kernel source code file a kernel developer sees a lone #else or #endif: ... #else ... It's not obvious at a glance what those preprocessor blocks are conditional on, if the starting #ifdef is outside visible range. So apply the standard pattern we use in such cases elsewhere in the kernel for large preprocessor blocks: #ifdef CONFIG_XXX ... ... ... #endif /* CONFIG_XXX */ ... #ifdef CONFIG_XXX ... ... ... #else /* !CONFIG_XXX: */ ... ... ... #endif /* !CONFIG_XXX */ ( Note that in the #else case we use the /* !CONFIG_XXX */ marker in the final #endif, not /* CONFIG_XXX */, which serves as an easy visual marker to differentiate #else or #elif related #endif closures from singular #ifdef/#endif blocks. ) Also clean up __CFI_DEFAULT definition with a bit more vertical alignment applied, and a pointless tab converted to the standard space we use in such definitions. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
2025-02-26x86/ibt: Add exact_endbr() helperPeter Zijlstra
For when we want to exactly match ENDBR, and not everything that we can scribble it with. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124200.059556588@infradead.org
2025-02-26x86/cfi: Add 'cfi=warn' boot optionPeter Zijlstra
Rebuilding with CONFIG_CFI_PERMISSIVE=y enabled is such a pain, esp. since clang is so slow. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124159.924496481@infradead.org
2025-02-14x86/ibt: Handle FineIBT in handle_cfi_failure()Peter Zijlstra
Sami reminded me that FineIBT failure does not hook into the regular CFI failure case, and as such CFI_PERMISSIVE does not work. Reported-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lkml.kernel.org/r/20250214092619.GB21726@noisy.programming.kicks-ass.net
2025-02-14x86/ibt: Clean up poison_endbr()Peter Zijlstra
Basically, get rid of the .warn argument and explicitly don't call the function when we know there isn't an endbr. This makes the calling code clearer. Note: perhaps don't add functions to .cfi_sites when the function doesn't have endbr -- OTOH why would the compiler emit the prefix if it has already determined there are no indirect callers and has omitted the ENDBR instruction. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lore.kernel.org/r/20250207122546.815505775@infradead.org
2025-02-14x86/alternative: Simplify callthunk patchingPeter Zijlstra
Now that paravirt call patching is implemented using alternatives, it is possible to avoid having to patch the alternative sites by including the altinstr_replacement calls in the call_sites list. This means we're now stacking relative adjustments like so: callthunks_patch_builtin_calls(): patches all function calls to target: func() -> func()-10 since the CALL accounting lives in the CALL_PADDING. This explicitly includes .altinstr_replacement alt_replace_call(): patches: x86_BUG() -> target() this patching is done in a relative manner, and will preserve the above adjustment, meaning that with calldepth patching it will do: x86_BUG()-10 -> target()-10 apply_relocation(): does code relocation, and adjusts all RIP-relative instructions to the new location, also in a relative manner. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lore.kernel.org/r/20250207122546.617187089@infradead.org
2025-02-14x86/cfi: Clean up linkagePeter Zijlstra
With the introduction of kCFI the addition of ENDBR to SYM_FUNC_START* no longer suffices to make the function indirectly callable. This now requires the use of SYM_TYPED_FUNC_START. As such, remove the implicit ENDBR from SYM_FUNC_START* and add some explicit annotations to fix things up again. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lore.kernel.org/r/20250207122546.409116003@infradead.org
2025-02-14x86/ibt: Clean up is_endbr()Peter Zijlstra
Pretty much every caller of is_endbr() actually wants to test something at an address and ends up doing get_kernel_nofault(). Fold the lot into a more convenient helper. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20250207122546.181367417@infradead.org
2025-02-03Revert "x86/module: prepare module loading for ROX allocations of text"Mike Rapoport (Microsoft)
The module code does not create a writable copy of the executable memory anymore so there is no need to handle it in module relocation and alternatives patching. This reverts commit 9bfc4824fd4836c16bb44f922bfaffba5da3e4f3. Signed-off-by: "Mike Rapoport (Microsoft)" <rppt@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250126074733.1384926-8-rppt@kernel.org
2024-12-20Merge branch 'linus' into x86/mm, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-11-19x86/mm/tlb: Update mm_cpumask lazilyRik van Riel
On busy multi-threaded workloads, there can be significant contention on the mm_cpumask at context switch time. Reduce that contention by updating mm_cpumask lazily, setting the CPU bit at context switch time (if not already set), and clearing the CPU bit at the first TLB flush sent to a CPU where the process isn't running. When a flurry of TLB flushes for a process happen, only the first one will be sent to CPUs where the process isn't running. The others will be sent to CPUs where the process is currently running. On an AMD Milan system with 36 cores, there is a noticeable difference: $ hackbench --groups 20 --loops 10000 Before: ~4.5s +/- 0.1s After: ~4.2s +/- 0.1s Signed-off-by: Rik van Riel <riel@surriel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Link: https://lore.kernel.org/r/20241114152723.1294686-2-riel@surriel.com
2024-11-07x86/module: prepare module loading for ROX allocations of textMike Rapoport (Microsoft)
When module text memory will be allocated with ROX permissions, the memory at the actual address where the module will live will contain invalid instructions and there will be a writable copy that contains the actual module code. Update relocations and alternatives patching to deal with it. [rppt@kernel.org: fix writable address in cfi_rewrite_endbr()] Link: https://lkml.kernel.org/r/ZysRwR29Ji8CcbXc@kernel.org Link: https://lkml.kernel.org/r/20241023162711.2579610-7-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Tested-by: kdevops <kdevops@lists.linux.dev> Tested-by: Nathan Chancellor <nathan@kernel.org> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Brian Cain <bcain@quicinc.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@armlinux.org.uk> Cc: Song Liu <song@kernel.org> Cc: Stafford Horne <shorne@gmail.com> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-16Merge tag 'hardening-v6.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - lkdtm/bugs: add test for hung smp_call_function_single() (Mark Rutland) - gcc-plugins: Remove duplicate included header file stringpool.h (Thorsten Blum) - ARM: Remove address checking for MMUless devices (Yanjun Yang) - randomize_kstack: Clean up per-arch entropy and codegen - KCFI: Make FineIBT mode Kconfig selectable - fortify: Do not special-case 0-sized destinations * tag 'hardening-v6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: randomize_kstack: Improve stack alignment codegen ARM: Remove address checking for MMUless devices gcc-plugins: Remove duplicate included header file stringpool.h randomize_kstack: Remove non-functional per-arch entropy filtering fortify: Do not special-case 0-sized destinations x86/alternatives: Make FineIBT mode Kconfig selectable lkdtm/bugs: add test for hung smp_call_function_single()
2024-07-01x86/alternatives, kvm: Fix a couple of CALLs without a frame pointerBorislav Petkov (AMD)
objtool complains: arch/x86/kvm/kvm.o: warning: objtool: .altinstr_replacement+0xc5: call without frame pointer save/setup vmlinux.o: warning: objtool: .altinstr_replacement+0x2eb: call without frame pointer save/setup Make sure %rSP is an output operand to the respective asm() statements. The test_cc() hunk and ALT_OUTPUT_SP() courtesy of peterz. Also from him add some helpful debugging info to the documentation. Now on to the explanations: tl;dr: The alternatives macros are pretty fragile. If I do ALT_OUTPUT_SP(output) in order to be able to package in a %rsp reference for objtool so that a stack frame gets properly generated, the inline asm input operand with positional argument 0 in clear_page(): "0" (page) gets "renumbered" due to the added : "+r" (current_stack_pointer), "=D" (page) and then gcc says: ./arch/x86/include/asm/page_64.h:53:9: error: inconsistent operand constraints in an ‘asm’ The fix is to use an explicit "D" constraint which points to a singleton register class (gcc terminology) which ends up doing what is expected here: the page pointer - input and output - should be in the same %rdi register. Other register classes have more than one register in them - example: "r" and "=r" or "A": ‘A’ The ‘a’ and ‘d’ registers. This class is used for instructions that return double word results in the ‘ax:dx’ register pair. Single word values will be allocated either in ‘ax’ or ‘dx’. so using "D" and "=D" just works in this particular case. And yes, one would say, sure, why don't you do "+D" but then: : "+r" (current_stack_pointer), "+D" (page) : [old] "i" (clear_page_orig), [new1] "i" (clear_page_rep), [new2] "i" (clear_page_erms), : "cc", "memory", "rax", "rcx") now find the Waldo^Wcomma which throws a wrench into all this. Because that silly macro has an "input..." consume-all last macro arg and in it, one is supposed to supply input *and* clobbers, leading to silly syntax snafus. Yap, they need to be cleaned up, one fine day... Closes: https://lore.kernel.org/oe-kbuild-all/202406141648.jO9qNGLa-lkp@intel.com/ Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Sean Christopherson <seanjc@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20240625112056.GDZnqoGDXgYuWBDUwu@fat_crate.local
2024-06-19x86/alternatives: Make FineIBT mode Kconfig selectableKees Cook
Since FineIBT performs checking at the destination, it is weaker against attacks that can construct arbitrary executable memory contents. As such, some system builders want to run with FineIBT disabled by default. Allow the "cfi=kcfi" boot param mode to be selectable through Kconfig via the newly introduced CONFIG_CFI_AUTO_DEFAULT. Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20240501000218.work.998-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
2024-06-11x86/alternatives: Add nested alternatives macrosPeter Zijlstra
Instead of making increasingly complicated ALTERNATIVE_n() implementations, use a nested alternative expression. The only difference between: ALTERNATIVE_2(oldinst, newinst1, flag1, newinst2, flag2) and ALTERNATIVE(ALTERNATIVE(oldinst, newinst1, flag1), newinst2, flag2) is that the outer alternative can add additional padding when the inner alternative is the shorter one, which then results in alt_instr::instrlen being inconsistent. However, this is easily remedied since the alt_instr entries will be consecutive and it is trivial to compute the max(alt_instr::instrlen) at runtime while patching. Specifically, after this the ALTERNATIVE_2 macro, after CPP expansion (and manual layout), looks like this: .macro ALTERNATIVE_2 oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2 740: 740: \oldinstr ; 741: .skip -(((744f-743f)-(741b-740b)) > 0) * ((744f-743f)-(741b-740b)),0x90 ; 742: .pushsection .altinstructions,"a" ; altinstr_entry 740b,743f,\ft_flags1,742b-740b,744f-743f ; .popsection ; .pushsection .altinstr_replacement,"ax" ; 743: \newinstr1 ; 744: .popsection ; ; 741: .skip -(((744f-743f)-(741b-740b)) > 0) * ((744f-743f)-(741b-740b)),0x90 ; 742: .pushsection .altinstructions,"a" ; altinstr_entry 740b,743f,\ft_flags2,742b-740b,744f-743f ; .popsection ; .pushsection .altinstr_replacement,"ax" ; 743: \newinstr2 ; 744: .popsection ; .endm The only label that is ambiguous is 740, however they all reference the same spot, so that doesn't matter. NOTE: obviously only @oldinstr may be an alternative; making @newinstr an alternative would mean patching .altinstr_replacement which very likely isn't what is intended, also the labels will be confused in that case. [ bp: Debug an issue where it would match the wrong two insns and and consider them nested due to the same signed offsets in the .alternative section and use instr_va() to compare the full virtual addresses instead. - Use new labels to denote that the new, nested alternatives are being used when staring at preprocessed output. - Use the %c constraint everywhere instead of %P and document the difference for future reference. ] Signed-off-by: Peter Zijlstra <peterz@infradead.org> Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230628104952.GA2439977@hirez.programming.kicks-ass.net
2024-05-17x86/alternatives: Use the correct length when optimizing NOPsBorislav Petkov (AMD)
Commit in Fixes moved the optimize_nops() call inside apply_relocation() and made it a second optimization pass after the relocations have been done. Since optimize_nops() works only on NOPs, that is fine and it'll simply jump over instructions which are not NOPs. However, it made that call with repl_len as the buffer length to optimize. However, it can happen that there are alternatives calls like this one: alternative("mfence; lfence", "", ALT_NOT(X86_FEATURE_APIC_MSRS_FENCE)); where the replacement length is 0. And using repl_len is wrong because apply_alternatives() expands the buffer size to the length of the source insn that is being patched, by padding it with one-byte NOPs: for (; insn_buff_sz < a->instrlen; insn_buff_sz++) insn_buff[insn_buff_sz] = 0x90; Long story short: pass the length of the original instruction(s) as the length of the temporary buffer which to optimize. Result: SMP alternatives: feat: 11*32+27, old: (lapic_next_deadline+0x9/0x50 (ffffffff81061829) len: 6), repl: (ffffffff89b1cc60, len: 0) flags: 0x1 SMP alternatives: ffffffff81061829: old_insn: 0f ae f0 0f ae e8 SMP alternatives: ffffffff81061829: final_insn: 90 90 90 90 90 90 => SMP alternatives: feat: 11*32+27, old: (lapic_next_deadline+0x9/0x50 (ffffffff81061839) len: 6), repl: (ffffffff89b1cc60, len: 0) flags: 0x1 SMP alternatives: ffffffff81061839: [0:6) optimized NOPs: 66 0f 1f 44 00 00 SMP alternatives: ffffffff81061839: old_insn: 0f ae f0 0f ae e8 SMP alternatives: ffffffff81061839: final_insn: 66 0f 1f 44 00 00 Fixes: da8f9cf7e721 ("x86/alternatives: Get rid of __optimize_nops()") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240515104804.32004-1-bp@kernel.org
2024-04-09x86/alternatives: Sort local vars in apply_alternatives()Borislav Petkov (AMD)
In a reverse x-mas tree. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240130105941.19707-5-bp@alien8.de
2024-04-09x86/alternatives: Optimize optimize_nops()Borislav Petkov (AMD)
Return early if NOPs have already been optimized. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240130105941.19707-4-bp@alien8.de
2024-04-09x86/alternatives: Get rid of __optimize_nops()Borislav Petkov (AMD)
There's no need to carve out bits of the NOP optimization functionality and look at JMP opcodes - simply do one more NOPs optimization pass at the end of patching. A lot simpler code. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240130105941.19707-3-bp@alien8.de
2024-04-09x86/alternatives: Use a temporary buffer when optimizing NOPsBorislav Petkov (AMD)
Instead of optimizing NOPs in-place, use a temporary buffer like the usual alternatives patching flow does. This obviates the need to grab locks when patching, see 6778977590da ("x86/alternatives: Disable interrupts and sync when optimizing NOPs in place") While at it, add nomenclature definitions clarifying and simplifying the naming of function-local variables in the alternatives code. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240130105941.19707-2-bp@alien8.de
2024-03-14Merge tag 'mm-stable-2024-03-13-20-04' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames from hotplugged memory rather than only from main memory. Series "implement "memmap on memory" feature on s390". - More folio conversions from Matthew Wilcox in the series "Convert memcontrol charge moving to use folios" "mm: convert mm counter to take a folio" - Chengming Zhou has optimized zswap's rbtree locking, providing significant reductions in system time and modest but measurable reductions in overall runtimes. The series is "mm/zswap: optimize the scalability of zswap rb-tree". - Chengming Zhou has also provided the series "mm/zswap: optimize zswap lru list" which provides measurable runtime benefits in some swap-intensive situations. - And Chengming Zhou further optimizes zswap in the series "mm/zswap: optimize for dynamic zswap_pools". Measured improvements are modest. - zswap cleanups and simplifications from Yosry Ahmed in the series "mm: zswap: simplify zswap_swapoff()". - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has contributed several DAX cleanups as well as adding a sysfs tunable to control the memmap_on_memory setting when the dax device is hotplugged as system memory. - Johannes Weiner has added the large series "mm: zswap: cleanups", which does that. - More DAMON work from SeongJae Park in the series "mm/damon: make DAMON debugfs interface deprecation unignorable" "selftests/damon: add more tests for core functionalities and corner cases" "Docs/mm/damon: misc readability improvements" "mm/damon: let DAMOS feeds and tame/auto-tune itself" - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs extension" Rakie Kim has developed a new mempolicy interleaving policy wherein we allocate memory across nodes in a weighted fashion rather than uniformly. This is beneficial in heterogeneous memory environments appearing with CXL. - Christophe Leroy has contributed some cleanup and consolidation work against the ARM pagetable dumping code in the series "mm: ptdump: Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute". - Luis Chamberlain has added some additional xarray selftesting in the series "test_xarray: advanced API multi-index tests". - Muhammad Usama Anjum has reworked the selftest code to make its human-readable output conform to the TAP ("Test Anything Protocol") format. Amongst other things, this opens up the use of third-party tools to parse and process out selftesting results. - Ryan Roberts has added fork()-time PTE batching of THP ptes in the series "mm/memory: optimize fork() with PTE-mapped THP". Mainly targeted at arm64, this significantly speeds up fork() when the process has a large number of pte-mapped folios. - David Hildenbrand also gets in on the THP pte batching game in his series "mm/memory: optimize unmap/zap with PTE-mapped THP". It implements batching during munmap() and other pte teardown situations. The microbenchmark improvements are nice. - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte mappings"). Kernel build times on arm64 improved nicely. Ryan's series "Address some contpte nits" provides some followup work. - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has fixed an obscure hugetlb race which was causing unnecessary page faults. He has also added a reproducer under the selftest code. - In the series "selftests/mm: Output cleanups for the compaction test", Mark Brown did what the title claims. - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring". - Even more zswap material from Nhat Pham. The series "fix and extend zswap kselftests" does as claimed. - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in our handling of DAX on archiecctures which have virtually aliasing data caches. The arm architecture is the main beneficiary. - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic improvements in worst-case mmap_lock hold times during certain userfaultfd operations. - Some page_owner enhancements and maintenance work from Oscar Salvador in his series "page_owner: print stacks and their outstanding allocations" "page_owner: Fixup and cleanup" - Uladzislau Rezki has contributed some vmalloc scalability improvements in his series "Mitigate a vmap lock contention". It realizes a 12x improvement for a certain microbenchmark. - Some kexec/crash cleanup work from Baoquan He in the series "Split crash out from kexec and clean up related config items". - Some zsmalloc maintenance work from Chengming Zhou in the series "mm/zsmalloc: fix and optimize objects/page migration" "mm/zsmalloc: some cleanup for get/set_zspage_mapping()" - Zi Yan has taught the MM to perform compaction on folios larger than order=0. This a step along the path to implementaton of the merging of large anonymous folios. The series is named "Enable >0 order folio memory compaction". - Christoph Hellwig has done quite a lot of cleanup work in the pagecache writeback code in his series "convert write_cache_pages() to an iterator". - Some modest hugetlb cleanups and speedups in Vishal Moola's series "Handle hugetlb faults under the VMA lock". - Zi Yan has changed the page splitting code so we can split huge pages into sizes other than order-0 to better utilize large folios. The series is named "Split a folio to any lower order folios". - David Hildenbrand has contributed the series "mm: remove total_mapcount()", a cleanup. - Matthew Wilcox has sought to improve the performance of bulk memory freeing in his series "Rearrange batched folio freeing". - Gang Li's series "hugetlb: parallelize hugetlb page init on boot" provides large improvements in bootup times on large machines which are configured to use large numbers of hugetlb pages. - Matthew Wilcox's series "PageFlags cleanups" does that. - Qi Zheng's series "minor fixes and supplement for ptdesc" does that also. S390 is affected. - Cleanups to our pagemap utility functions from Peter Xu in his series "mm/treewide: Replace pXd_large() with pXd_leaf()". - Nico Pache has fixed a few things with our hugepage selftests in his series "selftests/mm: Improve Hugepage Test Handling in MM Selftests". - Also, of course, many singleton patches to many things. Please see the individual changelogs for details. * tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits) mm/zswap: remove the memcpy if acomp is not sleepable crypto: introduce: acomp_is_async to expose if comp drivers might sleep memtest: use {READ,WRITE}_ONCE in memory scanning mm: prohibit the last subpage from reusing the entire large folio mm: recover pud_leaf() definitions in nopmd case selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements selftests/mm: skip uffd hugetlb tests with insufficient hugepages selftests/mm: dont fail testsuite due to a lack of hugepages mm/huge_memory: skip invalid debugfs new_order input for folio split mm/huge_memory: check new folio order when split a folio mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure mm: add an explicit smp_wmb() to UFFDIO_CONTINUE mm: fix list corruption in put_pages_list mm: remove folio from deferred split list before uncharging it filemap: avoid unnecessary major faults in filemap_fault() mm,page_owner: drop unnecessary check mm,page_owner: check for null stack_record before bumping its refcount mm: swap: fix race between free_swap_and_cache() and swapoff() mm/treewide: align up pXd_leaf() retval across archs mm/treewide: drop pXd_large() ...
2024-02-22x86/mm: delete unused cpu argument to leave_mm()Yosry Ahmed
The argument is unused since commit 3d28ebceaffa ("x86/mm: Rework lazy TLB to track the actual loaded mm"), delete it. Link: https://lkml.kernel.org/r/20240126080644.1714297-1-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-14Merge branch 'x86/bugs' into x86/core, to pick up pending changes before ↵Ingo Molnar
dependent patches Merge in pending alternatives patching infrastructure changes, before applying more patches. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-02-14Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the ↵Ingo Molnar
branch Conflicts: arch/x86/include/asm/percpu.h arch/x86/include/asm/text-patching.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-01-22x86/paravirt: Make BUG_func() usable by non-GPL modulesJuergen Gross
Several inlined functions subject to paravirt patching are referencing BUG_func() after the recent switch to the alternative patching mechanism. As those functions can legally be used by non-GPL modules, BUG_func() must be usable by those modules, too. So use EXPORT_SYMBOL() when exporting BUG_func(). Fixes: 9824b00c2b58 ("x86/paravirt: Move some functions and defines to alternative.c") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240109082232.22657-1-jgross@suse.com
2024-01-11Merge tag 'net-next-6.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "The most interesting thing is probably the networking structs reorganization and a significant amount of changes is around self-tests. Core & protocols: - Analyze and reorganize core networking structs (socks, netdev, netns, mibs) to optimize cacheline consumption and set up build time warnings to safeguard against future header changes This improves TCP performances with many concurrent connections up to 40% - Add page-pool netlink-based introspection, exposing the memory usage and recycling stats. This helps indentify bad PP users and possible leaks - Refine TCP/DCCP source port selection to no longer favor even source port at connect() time when IP_LOCAL_PORT_RANGE is set. This lowers the time taken by connect() for hosts having many active connections to the same destination - Refactor the TCP bind conflict code, shrinking related socket structs - Refactor TCP SYN-Cookie handling, as a preparation step to allow arbitrary SYN-Cookie processing via eBPF - Tune optmem_max for 0-copy usage, increasing the default value to 128KB and namespecifying it - Allow coalescing for cloned skbs coming from page pools, improving RX performances with some common configurations - Reduce extension header parsing overhead at GRO time - Add bridge MDB bulk deletion support, allowing user-space to request the deletion of matching entries - Reorder nftables struct members, to keep data accessed by the datapath first - Introduce TC block ports tracking and use. This allows supporting multicast-like behavior at the TC layer - Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and classifiers (RSVP and tcindex) - More data-race annotations - Extend the diag interface to dump TCP bound-only sockets - Conditional notification of events for TC qdisc class and actions - Support for WPAN dynamic associations with nearby devices, to form a sub-network using a specific PAN ID - Implement SMCv2.1 virtual ISM device support - Add support for Batman-avd mulicast packet type BPF: - Tons of verifier improvements: - BPF register bounds logic and range support along with a large test suite - log improvements - complete precision tracking support for register spills - track aligned STACK_ZERO cases as imprecise spilled registers. This improves the verifier "instructions processed" metric from single digit to 50-60% for some programs - support for user's global BPF subprogram arguments with few commonly requested annotations for a better developer experience - support tracking of BPF_JNE which helps cases when the compiler transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the like - several fixes - Add initial TX metadata implementation for AF_XDP with support in mlx5 and stmmac drivers. Two types of offloads are supported right now, that is, TX timestamp and TX checksum offload - Fix kCFI bugs in BPF all forms of indirect calls from BPF into kernel and from kernel into BPF work with CFI enabled. This allows BPF to work with CONFIG_FINEIBT=y - Change BPF verifier logic to validate global subprograms lazily instead of unconditionally before the main program, so they can be guarded using BPF CO-RE techniques - Support uid/gid options when mounting bpffs - Add a new kfunc which acquires the associated cgroup of a task within a specific cgroup v1 hierarchy where the latter is identified by its id - Extend verifier to allow bpf_refcount_acquire() of a map value field obtained via direct load which is a use-case needed in sched_ext - Add BPF link_info support for uprobe multi link along with bpftool integration for the latter - Support for VLAN tag in XDP hints - Remove deprecated bpfilter kernel leftovers given the project is developed in user-space (https://github.com/facebook/bpfilter) Misc: - Support for parellel TC self-tests execution - Increase MPTCP self-tests coverage - Updated the bridge documentation, including several so-far undocumented features - Convert all the net self-tests to run in unique netns, to avoid random failures due to conflict and allow concurrent runs - Add TCP-AO self-tests - Add kunit tests for both cfg80211 and mac80211 - Autogenerate Netlink families documentation from YAML spec - Add yml-gen support for fixed headers and recursive nests, the tool can now generate user-space code for all genetlink families for which we have specs - A bunch of additional module descriptions fixes - Catch incorrect freeing of pages belonging to a page pool Driver API: - Rust abstractions for network PHY drivers; do not cover yet the full C API, but already allow implementing functional PHY drivers in rust - Introduce queue and NAPI support in the netdev Netlink interface, allowing complete access to the device <> NAPIs <> queues relationship - Introduce notifications filtering for devlink to allow control application scale to thousands of instances - Improve PHY validation, requesting rate matching information for each ethtool link mode supported by both the PHY and host - Add support for ethtool symmetric-xor RSS hash - ACPI based Wifi band RFI (WBRF) mitigation feature for the AMD platform - Expose pin fractional frequency offset value over new DPLL generic netlink attribute - Convert older drivers to platform remove callback returning void - Add support for PHY package MMD read/write New hardware / drivers: - Ethernet: - Octeon CN10K devices - Broadcom 5760X P7 - Qualcomm SM8550 SoC - Texas Instrument DP83TG720S PHY - Bluetooth: - IMC Networks Bluetooth radio Removed: - WiFi: - libertas 16-bit PCMCIA support - Atmel at76c50x drivers - HostAP ISA/PCMCIA style 802.11b driver - zd1201 802.11b USB dongles - Orinoco ISA/PCMCIA 802.11b driver - Aviator/Raytheon driver - Planet WL3501 driver - RNDIS USB 802.11b driver Driver updates: - Ethernet high-speed NICs: - Intel (100G, ice, idpf): - allow one by one port representors creation and removal - add temperature and clock information reporting - add get/set for ethtool's header split ringparam - add again FW logging - adds support switchdev hardware packet mirroring - iavf: implement symmetric-xor RSS hash - igc: add support for concurrent physical and free-running timers - i40e: increase the allowable descriptors - nVidia/Mellanox: - Preparation for Socket-Direct multi-dev netdev. That will allow in future releases combining multiple PFs devices attached to different NUMA nodes under the same netdev - Broadcom (bnxt): - TX completion handling improvements - add basic ntuple filter support - reduce MSIX vectors usage for MQPRIO offload - add VXLAN support, USO offload and TX coalesce completion for P7 - Marvell Octeon EP: - xmit-more support - add PF-VF mailbox support and use it for FW notifications for VFs - Wangxun (ngbe/txgbe): - implement ethtool functions to operate pause param, ring param, coalesce channel number and msglevel - Netronome/Corigine (nfp): - add flow-steering support - support UDP segmentation offload - Ethernet NICs embedded, slower, virtual: - Xilinx AXI: remove duplicate DMA code adopting the dma engine driver - stmmac: add support for HW-accelerated VLAN stripping - TI AM654x sw: add mqprio, frame preemption & coalescing - gve: add support for non-4k page sizes. - virtio-net: support dynamic coalescing moderation - nVidia/Mellanox Ethernet datacenter switches: - allow firmware upgrade without a reboot - more flexible support for bridge flooding via the compressed FID flooding mode - Ethernet embedded switches: - Microchip: - fine-tune flow control and speed configurations in KSZ8xxx - KSZ88X3: enable setting rmii reference - Renesas: - add jumbo frames support - Marvell: - 88E6xxx: add "eth-mac" and "rmon" stats support - Ethernet PHYs: - aquantia: add firmware load support - at803x: refactor the driver to simplify adding support for more chip variants - NXP C45 TJA11xx: Add MACsec offload support - Wifi: - MediaTek (mt76): - NVMEM EEPROM improvements - mt7996 Extremely High Throughput (EHT) improvements - mt7996 Wireless Ethernet Dispatcher (WED) support - mt7996 36-bit DMA support - Qualcomm (ath12k): - support for a single MSI vector - WCN7850: support AP mode - Intel (iwlwifi): - new debugfs file fw_dbg_clear - allow concurrent P2P operation on DFS channels - Bluetooth: - QCA2066: support HFP offload - ISO: more broadcast-related improvements - NXP: better recovery in case receiver/transmitter get out of sync" * tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1714 commits) lan78xx: remove redundant statement in lan78xx_get_eee lan743x: remove redundant statement in lan743x_ethtool_get_eee bnxt_en: Fix RCU locking for ntuple filters in bnxt_rx_flow_steer() bnxt_en: Fix RCU locking for ntuple filters in bnxt_srxclsrldel() bnxt_en: Remove unneeded variable in bnxt_hwrm_clear_vnic_filter() tcp: Revert no longer abort SYN_SENT when receiving some ICMP Revert "mlx5 updates 2023-12-20" Revert "net: stmmac: Enable Per DMA Channel interrupt" ipvlan: Remove usage of the deprecated ida_simple_xx() API ipvlan: Fix a typo in a comment net/sched: Remove ipt action tests net: stmmac: Use interrupt mode INTM=1 for per channel irq net: stmmac: Add support for TX/RX channel interrupt net: stmmac: Make MSI interrupt routine generic dt-bindings: net: snps,dwmac: per channel irq net: phy: at803x: make read_status more generic net: phy: at803x: add support for cdt cross short test for qca808x net: phy: at803x: refactor qca808x cable test get status function net: phy: at803x: generalize cdt fault length function net: ethernet: cortina: Drop TSO support ...
2024-01-10x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNKBreno Leitao
Step 10/10 of the namespace unification of CPU mitigations related Kconfig options. [ mingo: Added one more case. ] Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-11-leitao@debian.org
2024-01-10x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLSBreno Leitao
Step 6/10 of the namespace unification of CPU mitigations related Kconfig options. Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-7-leitao@debian.org