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* Linux 6.9-rc4v6.9-rc4Linus Torvalds2024-04-141-1/+1
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* Merge tag 'pull-sysfs-annotation-fix' of ↵Linus Torvalds2024-04-141-1/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull sysfs fix from Al Viro: "Get rid of lockdep false positives around sysfs/overlayfs syzbot has uncovered a class of lockdep false positives for setups with sysfs being one of the backing layers in overlayfs. The root cause is that of->mutex allocated when opening a sysfs file read-only (which overlayfs might do) is confused with of->mutex of a file opened writable (held in write to sysfs file, which overlayfs won't do). Assigning them separate lockdep classes fixes that bunch and it's obviously safe" * tag 'pull-sysfs-annotation-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: kernfs: annotate different lockdep class for of->mutex of writable files
| * kernfs: annotate different lockdep class for of->mutex of writable filesAmir Goldstein2024-04-141-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The writable file /sys/power/resume may call vfs lookup helpers for arbitrary paths and readonly files can be read by overlayfs from vfs helpers when sysfs is a lower layer of overalyfs. To avoid a lockdep warning of circular dependency between overlayfs inode lock and kernfs of->mutex, use a different lockdep class for writable and readonly kernfs files. Reported-by: syzbot+9a5b0ced8b1bfb238b56@syzkaller.appspotmail.com Fixes: 0fedefd4c4e3 ("kernfs: sysfs: support custom llseek method for sysfs entries") Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge tag 'x86-urgent-2024-04-14' of ↵Linus Torvalds2024-04-1411-140/+131
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 fixes from Ingo Molnar: - Follow up fixes for the BHI mitigations code - Fix !SPECULATION_MITIGATIONS bug not turning off mitigations as expected - Work around an APIC emulation bug when the kernel is built with Clang and run as a SEV guest - Follow up x86 topology fixes * tag 'x86-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu/amd: Move TOPOEXT enablement into the topology parser x86/cpu/amd: Make the NODEID_MSR union actually work x86/cpu/amd: Make the CPUID 0x80000008 parser correct x86/bugs: Replace CONFIG_SPECTRE_BHI_{ON,OFF} with CONFIG_MITIGATION_SPECTRE_BHI x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=auto x86/bugs: Clarify that syscall hardening isn't a BHI mitigation x86/bugs: Fix BHI handling of RRSBA x86/bugs: Rename various 'ia32_cap' variables to 'x86_arch_cap_msr' x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIES x86/bugs: Fix BHI documentation x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n x86/topology: Don't update cpu_possible_map in topo_set_cpuids() x86/bugs: Fix return type of spectre_bhi_state() x86/apic: Force native_apic_mem_read() to use the MOV instruction
| * | x86/cpu/amd: Move TOPOEXT enablement into the topology parserThomas Gleixner2024-04-122-15/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The topology rework missed that early_init_amd() tries to re-enable the Topology Extensions when the BIOS disabled them. The new parser is invoked before early_init_amd() so the re-enable attempt happens too late. Move it into the AMD specific topology parser code where it belongs. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/878r1j260l.ffs@tglx
| * | x86/cpu/amd: Make the NODEID_MSR union actually workThomas Gleixner2024-04-121-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A system with NODEID_MSR was reported to crash during early boot without any output. The reason is that the union which is used for accessing the bitfields in the MSR is written wrongly and the resulting executable code accesses the wrong part of the MSR data. As a consequence a later division by that value results in 0 and that result is used for another division as divisor, which obviously does not work well. The magic world of C, unions and bitfields: union { u64 bita : 3, bitb : 3; u64 all; } x; x.all = foo(); a = x.bita; b = x.bitb; results in the effective executable code of: a = b = x.bita; because bita and bitb are treated as union members and therefore both end up at bit offset 0. Wrapping the bitfield into an anonymous struct: union { struct { u64 bita : 3, bitb : 3; }; u64 all; } x; works like expected. Rework the NODEID_MSR union in exactly that way to cure the problem. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Reported-by: "kernelci.org bot" <bot@kernelci.org> Reported-by: Laura Nao <laura.nao@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Laura Nao <laura.nao@collabora.com> Link: https://lore.kernel.org/r/20240410194311.596282919@linutronix.de Closes: https://lore.kernel.org/all/20240322175210.124416-1-laura.nao@collabora.com/
| * | x86/cpu/amd: Make the CPUID 0x80000008 parser correctThomas Gleixner2024-04-121-6/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CPUID 0x80000008 ECX.cpu_nthreads describes the number of threads in the package. The parser uses this value to initialize the SMT domain level. That's wrong because cpu_nthreads does not describe the number of threads per physical core. So this needs to set the CORE domain level and let the later parsers set the SMT shift if available. Preset the SMT domain level with the assumption of one thread per core, which is correct ifrt here are no other CPUID leafs to parse, and propagate cpu_nthreads and the core level APIC bitwidth into the CORE domain. Fixes: f7fb3b2dd92c ("x86/cpu: Provide an AMD/HYGON specific topology parser") Reported-by: "kernelci.org bot" <bot@kernelci.org> Reported-by: Laura Nao <laura.nao@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Laura Nao <laura.nao@collabora.com> Link: https://lore.kernel.org/r/20240410194311.535206450@linutronix.de
| * | x86/bugs: Replace CONFIG_SPECTRE_BHI_{ON,OFF} with CONFIG_MITIGATION_SPECTRE_BHIJosh Poimboeuf2024-04-122-15/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For consistency with the other CONFIG_MITIGATION_* options, replace the CONFIG_SPECTRE_BHI_{ON,OFF} options with a single CONFIG_MITIGATION_SPECTRE_BHI option. [ mingo: Fix ] Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nikolay Borisov <nik.borisov@suse.com> Link: https://lore.kernel.org/r/3833812ea63e7fdbe36bf8b932e63f70d18e2a2a.1712813475.git.jpoimboe@kernel.org
| * | x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=autoJosh Poimboeuf2024-04-124-21/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unlike most other mitigations' "auto" options, spectre_bhi=auto only mitigates newer systems, which is confusing and not particularly useful. Remove it. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/412e9dc87971b622bbbaf64740ebc1f140bff343.1712813475.git.jpoimboe@kernel.org
| * | x86/bugs: Clarify that syscall hardening isn't a BHI mitigationJosh Poimboeuf2024-04-113-11/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While syscall hardening helps prevent some BHI attacks, there's still other low-hanging fruit remaining. Don't classify it as a mitigation and make it clear that the system may still be vulnerable if it doesn't have a HW or SW mitigation enabled. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/b5951dae3fdee7f1520d5136a27be3bdfe95f88b.1712813475.git.jpoimboe@kernel.org
| * | x86/bugs: Fix BHI handling of RRSBAJosh Poimboeuf2024-04-111-12/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ARCH_CAP_RRSBA check isn't correct: RRSBA may have already been disabled by the Spectre v2 mitigation (or can otherwise be disabled by the BHI mitigation itself if needed). In that case retpolines are fine. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/6f56f13da34a0834b69163467449be7f58f253dc.1712813475.git.jpoimboe@kernel.org
| * | x86/bugs: Rename various 'ia32_cap' variables to 'x86_arch_cap_msr'Ingo Molnar2024-04-113-42/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So we are using the 'ia32_cap' value in a number of places, which got its name from MSR_IA32_ARCH_CAPABILITIES MSR register. But there's very little 'IA32' about it - this isn't 32-bit only code, nor does it originate from there, it's just a historic quirk that many Intel MSR names are prefixed with IA32_. This is already clear from the helper method around the MSR: x86_read_arch_cap_msr(), which doesn't have the IA32 prefix. So rename 'ia32_cap' to 'x86_arch_cap_msr' to be consistent with its role and with the naming of the helper function. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Nikolay Borisov <nik.borisov@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org
| * | x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIESJosh Poimboeuf2024-04-111-15/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no need to keep reading MSR_IA32_ARCH_CAPABILITIES over and over. It's even read in the BHI sysfs function which is a big no-no. Just read it once and cache it. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org
| * | x86/bugs: Fix BHI documentationJosh Poimboeuf2024-04-112-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix up some inaccuracies in the BHI documentation. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/8c84f7451bfe0dd08543c6082a383f390d4aa7e2.1712813475.git.jpoimboe@kernel.org
| * | x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=nSean Christopherson2024-04-101-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Initialize cpu_mitigations to CPU_MITIGATIONS_OFF if the kernel is built with CONFIG_SPECULATION_MITIGATIONS=n, as the help text quite clearly states that disabling SPECULATION_MITIGATIONS is supposed to turn off all mitigations by default. │ If you say N, all mitigations will be disabled. You really │ should know what you are doing to say so. As is, the kernel still defaults to CPU_MITIGATIONS_AUTO, which results in some mitigations being enabled in spite of SPECULATION_MITIGATIONS=n. Fixes: f43b9876e857 ("x86/retbleed: Add fine grained Kconfig knobs") Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Cc: stable@vger.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20240409175108.1512861-2-seanjc@google.com
| * | x86/topology: Don't update cpu_possible_map in topo_set_cpuids()Thomas Gleixner2024-04-101-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | topo_set_cpuids() updates cpu_present_map and cpu_possible map. It is invoked during enumeration and "physical hotplug" operations. In the latter case this results in a kernel crash because cpu_possible_map is marked read only after init completes. There is no reason to update cpu_possible_map in that function. During enumeration cpu_possible_map is not relevant and gets fully initialized after enumeration completed. On "physical hotplug" the bit is already set because the kernel allows only CPUs to be plugged which have been enumerated and associated to a CPU number during early boot. Remove the bogus update of cpu_possible_map. Fixes: 0e53e7b656cf ("x86/cpu/topology: Sanitize the APIC admission logic") Reported-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/87ttkc6kwx.ffs@tglx
| * | x86/bugs: Fix return type of spectre_bhi_state()Daniel Sneddon2024-04-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The definition of spectre_bhi_state() incorrectly returns a const char * const. This causes the a compiler warning when building with W=1: warning: type qualifiers ignored on function return type [-Wignored-qualifiers] 2812 | static const char * const spectre_bhi_state(void) Remove the const qualifier from the pointer. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Reported-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20240409230806.1545822-1-daniel.sneddon@linux.intel.com
| * | Merge branch 'linus' into x86/urgent, to pick up dependent commitsIngo Molnar2024-04-1033-87/+463
| |\ \ | | | | | | | | | | | | | | | | | | | | Prepare to fix aspects of the new BHI code. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86/apic: Force native_apic_mem_read() to use the MOV instructionAdam Dunlap2024-04-081-1/+2
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When done from a virtual machine, instructions that touch APIC memory must be emulated. By convention, MMIO accesses are typically performed via io.h helpers such as readl() or writeq() to simplify instruction emulation/decoding (ex: in KVM hosts and SEV guests) [0]. Currently, native_apic_mem_read() does not follow this convention, allowing the compiler to emit instructions other than the MOV instruction generated by readl(). In particular, when the kernel is compiled with clang and run as a SEV-ES or SEV-SNP guest, the compiler would emit a TESTL instruction which is not supported by the SEV-ES emulator, causing a boot failure in that environment. It is likely the same problem would happen in a TDX guest as that uses the same instruction emulator as SEV-ES. To make sure all emulators can emulate APIC memory reads via MOV, use the readl() function in native_apic_mem_read(). It is expected that any emulator would support MOV in any addressing mode as it is the most generic and is what is usually emitted currently. The TESTL instruction is emitted when native_apic_mem_read() is inlined into apic_mem_wait_icr_idle(). The emulator comes from insn_decode_mmio() in arch/x86/lib/insn-eval.c. It's not worth it to extend insn_decode_mmio() to support more instructions since, in theory, the compiler could choose to output nearly any instruction for such reads which would bloat the emulator beyond reason. [0] https://lore.kernel.org/all/20220405232939.73860-12-kirill.shutemov@linux.intel.com/ [ bp: Massage commit message, fix typos. ] Signed-off-by: Adam Dunlap <acdunlap@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Kevin Loughlin <kevinloughlin@google.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20240318230927.2191933-1-acdunlap@google.com
* | | Merge tag 'timers-urgent-2024-04-14' of ↵Linus Torvalds2024-04-147-124/+147
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: - Address a (valid) W=1 build warning - Fix timer self-tests - Annotate a KCSAN warning wrt. accesses to the tick_do_timer_cpu global variable - Address a !CONFIG_BUG build warning * tag 'timers-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests: kselftest: Fix build failure with NOLIBC selftests: timers: Fix abs() warning in posix_timers test selftests: kselftest: Mark functions that unconditionally call exit() as __noreturn selftests: timers: Fix posix_timers ksft_print_msg() warning selftests: timers: Fix valid-adjtimex signed left-shift undefined behavior bug: Fix no-return-statement warning with !CONFIG_BUG timekeeping: Use READ/WRITE_ONCE() for tick_do_timer_cpu selftests/timers/posix_timers: Reimplement check_timer_distribution() irqflags: Explicitly ignore lockdep_hrtimer_exit() argument
| * | | selftests: kselftest: Fix build failure with NOLIBCOleg Nesterov2024-04-121-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Mark explains ksft_min_kernel_version() can't be compiled with nolibc, it doesn't implement uname(). Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()") Reported-by: Mark Brown <broonie@kernel.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240412123536.GA32444@redhat.com Closes: https://lore.kernel.org/all/f0523b3a-ea08-4615-b0fb-5b504a2d39df@sirena.org.uk/
| * | | selftests: timers: Fix abs() warning in posix_timers testJohn Stultz2024-04-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Building with clang results in the following warning: posix_timers.c:69:6: warning: absolute value function 'abs' given an argument of type 'long long' but has parameter of type 'int' which may cause truncation of value [-Wabsolute-value] if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^ So switch to using llabs() instead. Fixes: 0bc4b0cf1570 ("selftests: add basic posix timers selftests") Signed-off-by: John Stultz <jstultz@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240410232637.4135564-3-jstultz@google.com
| * | | selftests: kselftest: Mark functions that unconditionally call exit() as ↵Nathan Chancellor2024-04-121-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __noreturn After commit 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()"), clang warns: tools/testing/selftests/timers/../kselftest.h:398:6: warning: variable 'major' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized] 398 | if (uname(&info) || sscanf(info.release, "%u.%u.", &major, &minor) != 2) | ^~~~~~~~~~~~ tools/testing/selftests/timers/../kselftest.h:401:9: note: uninitialized use occurs here 401 | return major > min_major || (major == min_major && minor >= min_minor); | ^~~~~ tools/testing/selftests/timers/../kselftest.h:398:6: note: remove the '||' if its condition is always false 398 | if (uname(&info) || sscanf(info.release, "%u.%u.", &major, &minor) != 2) | ^~~~~~~~~~~~~~~ tools/testing/selftests/timers/../kselftest.h:395:20: note: initialize the variable 'major' to silence this warning 395 | unsigned int major, minor; | ^ | = 0 This is a false positive because if uname() fails, ksft_exit_fail_msg() will be called, which unconditionally calls exit(), a noreturn function. However, clang does not know that ksft_exit_fail_msg() will call exit() at the point in the pipeline that the warning is emitted because inlining has not occurred, so it assumes control flow will resume normally after ksft_exit_fail_msg() is called. Make it clear to clang that all of the functions that call exit() unconditionally in kselftest.h are noreturn transitively by marking them explicitly with '__attribute__((__noreturn__))', which clears up the warning above and any future warnings that may appear for the same reason. Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()") Reported-by: John Stultz <jstultz@google.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240411-mark-kselftest-exit-funcs-noreturn-v1-1-b027c948f586@kernel.org Closes: https://lore.kernel.org/all/20240410232637.4135564-2-jstultz@google.com/
| * | | selftests: timers: Fix posix_timers ksft_print_msg() warningJohn Stultz2024-04-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()") the following warning occurs when building with an older gcc: posix_timers.c:250:2: warning: format not a string literal and no format arguments [-Wformat-security] 250 | ksft_print_msg(errmsg); | ^~~~~~~~~~~~~~ Fix this up by changing it to ksft_print_msg("%s", errmsg) Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()") Signed-off-by: John Stultz <jstultz@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Justin Stitt <justinstitt@google.com> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240410232637.4135564-1-jstultz@google.com
| * | | selftests: timers: Fix valid-adjtimex signed left-shift undefined behaviorJohn Stultz2024-04-101-37/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The struct adjtimex freq field takes a signed value who's units are in shifted (<<16) parts-per-million. Unfortunately for negative adjustments, the straightforward use of: freq = ppm << 16 trips undefined behavior warnings with clang: valid-adjtimex.c:66:6: warning: shifting a negative signed value is undefined [-Wshift-negative-value] -499<<16, ~~~~^ valid-adjtimex.c:67:6: warning: shifting a negative signed value is undefined [-Wshift-negative-value] -450<<16, ~~~~^ .. Fix it by using a multiply by (1 << 16) instead of shifting negative values in the valid-adjtimex test case. Align the values for better readability. Reported-by: Lee Jones <joneslee@google.com> Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Signed-off-by: John Stultz <jstultz@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/20240409202222.2830476-1-jstultz@google.com Link: https://lore.kernel.org/lkml/0c6d4f0d-2064-4444-986b-1d1ed782135f@collabora.com/
| * | | bug: Fix no-return-statement warning with !CONFIG_BUGAdrian Hunter2024-04-101-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BUG() does not return, and arch implementations of BUG() use unreachable() or other non-returning code. However with !CONFIG_BUG, the default implementation is often used instead, and that does not do that. x86 always uses its own implementation, but powerpc with !CONFIG_BUG gives a build error: kernel/time/timekeeping.c: In function ‘timekeeping_debug_get_ns’: kernel/time/timekeeping.c:286:1: error: no return statement in function returning non-void [-Werror=return-type] Add unreachable() to default !CONFIG_BUG BUG() implementation. Fixes: e8e9d21a5df6 ("timekeeping: Refactor timekeeping helpers") Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Link: https://lore.kernel.org/r/20240410153212.127477-1-adrian.hunter@intel.com Closes: https://lore.kernel.org/all/CA+G9fYvjdZCW=7ZGxS6A_3bysjQ56YF7S-+PNLQ_8a4DKh1Bhg@mail.gmail.com/
| * | | timekeeping: Use READ/WRITE_ONCE() for tick_do_timer_cpuThomas Gleixner2024-04-102-22/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tick_do_timer_cpu is used lockless to check which CPU needs to take care of the per tick timekeeping duty. This is done to avoid a thundering herd problem on jiffies_lock. The read and writes are not annotated so KCSAN complains about data races: BUG: KCSAN: data-race in tick_nohz_idle_stop_tick / tick_nohz_next_event write to 0xffffffff8a2bda30 of 4 bytes by task 0 on cpu 26: tick_nohz_idle_stop_tick+0x3b1/0x4a0 do_idle+0x1e3/0x250 read to 0xffffffff8a2bda30 of 4 bytes by task 0 on cpu 16: tick_nohz_next_event+0xe7/0x1e0 tick_nohz_get_sleep_length+0xa7/0xe0 menu_select+0x82/0xb90 cpuidle_select+0x44/0x60 do_idle+0x1c2/0x250 value changed: 0x0000001a -> 0xffffffff Annotate them with READ/WRITE_ONCE() to document the intentional data race. Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Sean Anderson <sean.anderson@seco.com> Link: https://lore.kernel.org/r/87cyqy7rt3.ffs@tglx
| * | | selftests/timers/posix_timers: Reimplement check_timer_distribution()Oleg Nesterov2024-04-092-56/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | check_timer_distribution() runs ten threads in a busy loop and tries to test that the kernel distributes a process posix CPU timer signal to every thread over time. There is not guarantee that this is true even after commit bcb7ee79029d ("posix-timers: Prefer delivery of signals to the current thread") because that commit only avoids waking up the sleeping process leader thread, but that has nothing to do with the actual signal delivery. As the signal is process wide the first thread which observes sigpending and wins the race to lock sighand will deliver the signal. Testing shows that this hangs on a regular base because some threads never win the race. The comment "This primarily tests that the kernel does not favour any one." is wrong. The kernel does favour a thread which hits the timer interrupt when CLOCK_PROCESS_CPUTIME_ID expires. Rewrite the test so it only checks that the group leader sleeping in join() never receives SIGALRM and the thread which burns CPU cycles receives all signals. In older kernels which do not have commit bcb7ee79029d ("posix-timers: Prefer delivery of signals to the current thread") the test-case fails immediately, the very 1st tick wakes the leader up. Otherwise it quickly succeeds after 100 ticks. CI testing wants to use newer selftest versions on stable kernels. In this case the test is guaranteed to fail. So check in the failure case whether the kernel version is less than v6.3 and skip the test result in that case. [ tglx: Massaged change log, renamed the version check helper ] Fixes: e797203fb3ba ("selftests/timers/posix_timers: Test delivery of signals across threads") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240409133802.GD29396@redhat.com
| * | | irqflags: Explicitly ignore lockdep_hrtimer_exit() argumentArnd Bergmann2024-04-081-1/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building with 'make W=1' but CONFIG_TRACE_IRQFLAGS=n, the unused argument to lockdep_hrtimer_exit() causes a warning: kernel/time/hrtimer.c:1655:14: error: variable 'expires_in_hardirq' set but not used [-Werror=unused-but-set-variable] This is intentional behavior, so add a cast to void to shut up the warning. Fixes: 73d20564e0dc ("hrtimer: Don't dereference the hrtimer pointer after the callback") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240408074609.3170807-1-arnd@kernel.org Closes: https://lore.kernel.org/oe-kbuild-all/202311191229.55QXHVc6-lkp@intel.com/
* | | Merge tag 'perf-urgent-2024-04-14' of ↵Linus Torvalds2024-04-141-0/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf event fix from Ingo Molnar: "Fix the x86 PMU multi-counter code returning invalid data in certain circumstances" * tag 'perf-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix out of range data
| * | | perf/x86: Fix out of range dataNamhyung Kim2024-04-101-0/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x86 each struct cpu_hw_events maintains a table for counter assignment but it missed to update one for the deleted event in x86_pmu_del(). This can make perf_clear_dirty_counters() reset used counter if it's called before event scheduling or enabling. Then it would return out of range data which doesn't make sense. The following code can reproduce the problem. $ cat repro.c #include <pthread.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <linux/perf_event.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/syscall.h> struct perf_event_attr attr = { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES, .disabled = 1, }; void *worker(void *arg) { int cpu = (long)arg; int fd1 = syscall(SYS_perf_event_open, &attr, -1, cpu, -1, 0); int fd2 = syscall(SYS_perf_event_open, &attr, -1, cpu, -1, 0); void *p; do { ioctl(fd1, PERF_EVENT_IOC_ENABLE, 0); p = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd1, 0); ioctl(fd2, PERF_EVENT_IOC_ENABLE, 0); ioctl(fd2, PERF_EVENT_IOC_DISABLE, 0); munmap(p, 4096); ioctl(fd1, PERF_EVENT_IOC_DISABLE, 0); } while (1); return NULL; } int main(void) { int i; int n = sysconf(_SC_NPROCESSORS_ONLN); pthread_t *th = calloc(n, sizeof(*th)); for (i = 0; i < n; i++) pthread_create(&th[i], NULL, worker, (void *)(long)i); for (i = 0; i < n; i++) pthread_join(th[i], NULL); free(th); return 0; } And you can see the out of range data using perf stat like this. Probably it'd be easier to see on a large machine. $ gcc -o repro repro.c -pthread $ ./repro & $ sudo perf stat -A -I 1000 2>&1 | awk '{ if (length($3) > 15) print }' 1.001028462 CPU6 196,719,295,683,763 cycles # 194290.996 GHz (71.54%) 1.001028462 CPU3 396,077,485,787,730 branch-misses # 15804359784.80% of all branches (71.07%) 1.001028462 CPU17 197,608,350,727,877 branch-misses # 14594186554.56% of all branches (71.22%) 2.020064073 CPU4 198,372,472,612,140 cycles # 194681.113 GHz (70.95%) 2.020064073 CPU6 199,419,277,896,696 cycles # 195720.007 GHz (70.57%) 2.020064073 CPU20 198,147,174,025,639 cycles # 194474.654 GHz (71.03%) 2.020064073 CPU20 198,421,240,580,145 stalled-cycles-frontend # 100.14% frontend cycles idle (70.93%) 3.037443155 CPU4 197,382,689,923,416 cycles # 194043.065 GHz (71.30%) 3.037443155 CPU20 196,324,797,879,414 cycles # 193003.773 GHz (71.69%) 3.037443155 CPU5 197,679,956,608,205 stalled-cycles-backend # 1315606428.66% backend cycles idle (71.19%) 3.037443155 CPU5 198,571,860,474,851 instructions # 13215422.58 insn per cycle It should move the contents in the cpuc->assign as well. Fixes: 5471eea5d3bf ("perf/x86: Reset the dirty counter to prevent the leak for an RDPMC task") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240306061003.1894224-1-namhyung@kernel.org
* | | Merge tag 'locking-urgent-2024-04-14' of ↵Linus Torvalds2024-04-142-5/+5
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fix from Ingo Molnar: "Fix a PREEMPT_RT build bug" * tag 'locking-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking: Make rwsem_assert_held_write_nolockdep() build with PREEMPT_RT=y
| * | | locking: Make rwsem_assert_held_write_nolockdep() build with PREEMPT_RT=ySebastian Andrzej Siewior2024-04-082-5/+5
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit cited below broke the build for PREEMPT_RT because rwsem_assert_held_write_nolockdep() passes a struct rw_semaphore but rw_base_assert_held_write() expects struct rwbase_rt. Fixing the type alone leads to the problem that WARN_ON() is not found because bug.h is missing. In order to resolve this: - Keep the assert (WARN_ON()) in rwsem.h (not rwbase_rt.h) - Make rwsem_assert_held_write_nolockdep() do the implementation specific (rw_base) writer check. - Replace the "inline" with __always_inline which was used before. Fixes: f70405afc99b1 ("locking: Add rwsem_assert_held() and rwsem_assert_held_write()") Reported-by: Clark Williams <williams@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/r/20240319182050.U4AzUF3I@linutronix.de
* | | Merge tag 'irq-urgent-2024-04-14' of ↵Linus Torvalds2024-04-141-1/+7
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fix from Ingo Molnar: "Fix a bug in the GIC irqchip driver" * tag 'irq-urgent-2024-04-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/gic-v3-its: Fix VSYNC referencing an unmapped VPE on GIC v4.1
| * | | irqchip/gic-v3-its: Fix VSYNC referencing an unmapped VPE on GIC v4.1Nianyao Tang2024-04-091-1/+7
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As per the GICv4.1 spec (Arm IHI 0069H, 5.3.19): "A VMAPP with {V, Alloc}=={0, x} is self-synchronizing, This means the ITS command queue does not show the command as consumed until all of its effects are completed." Furthermore, VSYNC is allowed to deliver an SError when referencing a non existent VPE. By these definitions, a VMAPP followed by a VSYNC is a bug, as the later references a VPE that has been unmapped by the former. Fix it by eliding the VSYNC in this scenario. Fixes: 64edfaa9a234 ("irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP") Signed-off-by: Nianyao Tang <tangnianyao@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Link: https://lore.kernel.org/r/20240406022737.3898763-1-tangnianyao@huawei.com
* | | Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds2024-04-145-15/+40
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull virtio bugfixes from Michael Tsirkin: "Some small, obvious (in hindsight) bugfixes: - new ioctl in vhost-vdpa has a wrong # - not too late to fix - vhost has apparently been lacking an smp_rmb() - due to code duplication :( The duplication will be fixed in the next merge cycle, this is a minimal fix - an error message in vhost talks about guest moving used index - which of course never happens, guest only ever moves the available index - i2c-virtio didn't set the driver owner so it did not get refcounted correctly" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vhost: correct misleading printing information vhost-vdpa: change ioctl # for VDPA_GET_VRING_SIZE virtio: store owner from modules with register_virtio_driver() vhost: Add smp_rmb() in vhost_enable_notify() vhost: Add smp_rmb() in vhost_vq_avail_empty()
| * | | vhost: correct misleading printing informationXianting Tian2024-04-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Guest moved avail idx not used idx when we need to print log if '(vq->avail_idx - last_avail_idx) > vq->num', so fix it. Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com> Message-Id: <20240311082109.46773-1-xianting.tian@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
| * | | vhost-vdpa: change ioctl # for VDPA_GET_VRING_SIZEMichael S. Tsirkin2024-04-081-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | VDPA_GET_VRING_SIZE by mistake uses the already occupied ioctl # 0x80 and we never noticed - it happens to work because the direction and size are different, but confuses tools such as perf which like to look at just the number, and breaks the extra robustness of the ioctl numbering macros. To fix, sort the entries and renumber the ioctl - not too late since it wasn't in any released kernels yet. Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Reported-by: Namhyung Kim <namhyung@kernel.org> Fixes: 1496c47065f9 ("vhost-vdpa: uapi to support reporting per vq size") Cc: "Zhu Lingshan" <lingshan.zhu@intel.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <41c1c5489688abe5bfef9f7cf15584e3fb872ac5.1712092759.git.mst@redhat.com> Reviewed-by: Eugenio Pérez <eperezma@redhat.com> Reviewed-by: Zhu Lingshan <lingshan.zhu@intel.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
| * | | virtio: store owner from modules with register_virtio_driver()Krzysztof Kozlowski2024-04-083-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modules registering driver with register_virtio_driver() might forget to set .owner field. i2c-virtio.c for example has it missing. The field is used by some other kernel parts for reference counting (try_module_get()), so it is expected that drivers will set it. Solve the problem by moving this task away from the drivers to the core virtio code, just like we did for platform_driver in commit 9447057eaff8 ("platform_device: use a macro instead of platform_driver_register"). Fixes: 3cfc88380413 ("i2c: virtio: add a virtio i2c frontend driver") Cc: "Jie Deng" <jie.deng@intel.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Message-Id: <20240331-module-owner-virtio-v2-1-98f04bfaf46a@linaro.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
| * | | vhost: Add smp_rmb() in vhost_enable_notify()Gavin Shan2024-04-081-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A smp_rmb() has been missed in vhost_enable_notify(), inspired by Will. Otherwise, it's not ensured the available ring entries pushed by guest can be observed by vhost in time, leading to stale available ring entries fetched by vhost in vhost_get_vq_desc(), as reported by Yihuang Yu on NVidia's grace-hopper (ARM64) platform. /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64 \ -accel kvm -machine virt,gic-version=host -cpu host \ -smp maxcpus=1,cpus=1,sockets=1,clusters=1,cores=1,threads=1 \ -m 4096M,slots=16,maxmem=64G \ -object memory-backend-ram,id=mem0,size=4096M \ : \ -netdev tap,id=vnet0,vhost=true \ -device virtio-net-pci,bus=pcie.8,netdev=vnet0,mac=52:54:00:f1:26:b0 : guest# netperf -H 10.26.1.81 -l 60 -C -c -t UDP_STREAM virtio_net virtio0: output.0:id 100 is not a head! Add the missed smp_rmb() in vhost_enable_notify(). When it returns true, it means there's still pending tx buffers. Since it might read indices, so it still can bypass the smp_rmb() in vhost_get_vq_desc(). Note that it should be safe until vq->avail_idx is changed by commit d3bb267bbdcb ("vhost: cache avail index in vhost_enable_notify()"). Fixes: d3bb267bbdcb ("vhost: cache avail index in vhost_enable_notify()") Cc: <stable@kernel.org> # v5.18+ Reported-by: Yihuang Yu <yihyu@redhat.com> Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Gavin Shan <gshan@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Message-Id: <20240328002149.1141302-3-gshan@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
| * | | vhost: Add smp_rmb() in vhost_vq_avail_empty()Gavin Shan2024-04-081-1/+11
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A smp_rmb() has been missed in vhost_vq_avail_empty(), spotted by Will. Otherwise, it's not ensured the available ring entries pushed by guest can be observed by vhost in time, leading to stale available ring entries fetched by vhost in vhost_get_vq_desc(), as reported by Yihuang Yu on NVidia's grace-hopper (ARM64) platform. /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64 \ -accel kvm -machine virt,gic-version=host -cpu host \ -smp maxcpus=1,cpus=1,sockets=1,clusters=1,cores=1,threads=1 \ -m 4096M,slots=16,maxmem=64G \ -object memory-backend-ram,id=mem0,size=4096M \ : \ -netdev tap,id=vnet0,vhost=true \ -device virtio-net-pci,bus=pcie.8,netdev=vnet0,mac=52:54:00:f1:26:b0 : guest# netperf -H 10.26.1.81 -l 60 -C -c -t UDP_STREAM virtio_net virtio0: output.0:id 100 is not a head! Add the missed smp_rmb() in vhost_vq_avail_empty(). When tx_can_batch() returns true, it means there's still pending tx buffers. Since it might read indices, so it still can bypass the smp_rmb() in vhost_get_vq_desc(). Note that it should be safe until vq->avail_idx is changed by commit 275bf960ac697 ("vhost: better detection of available buffers"). Fixes: 275bf960ac69 ("vhost: better detection of available buffers") Cc: <stable@kernel.org> # v4.11+ Reported-by: Yihuang Yu <yihyu@redhat.com> Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Gavin Shan <gshan@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Message-Id: <20240328002149.1141302-2-gshan@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
* | | Merge tag 'dma-maping-6.9-2024-04-14' of ↵Linus Torvalds2024-04-141-33/+58
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping fixes from Christoph Hellwig: - fix up swiotlb buffer padding even more (Petr Tesarik) - fix for partial dma_sync on swiotlb (Michael Kelley) - swiotlb debugfs fix (Dexuan Cui) * tag 'dma-maping-6.9-2024-04-14' of git://git.infradead.org/users/hch/dma-mapping: swiotlb: do not set total_used to 0 in swiotlb_create_debugfs_files() swiotlb: fix swiotlb_bounce() to do partial sync's correctly swiotlb: extend buffer pre-padding to alloc_align_mask if necessary
| * | | swiotlb: do not set total_used to 0 in swiotlb_create_debugfs_files()Dexuan Cui2024-04-021-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes the readout of /sys/kernel/debug/swiotlb/io_tlb_used and io_tlb_used_hiwater can be a huge number (e.g. 18446744073709551615), which is actually a negative number if we use "%ld" to print the number. When swiotlb_create_default_debugfs() is running from late_initcall, mem->total_used may already be non-zero, because the storage driver may have already started to perform I/O operations: if the storage driver is built-in, its probe() callback is called before late_initcall. swiotlb_create_debugfs_files() should not blindly set mem->total_used and mem->used_hiwater to 0; actually it doesn't have to initialize the fields at all, because the fields, as part of the global struct io_tlb_default_mem, have been implicitly initialized to zero. Also don't explicitly set mem->transient_nslabs to 0. Fixes: 8b0977ecc8b3 ("swiotlb: track and report io_tlb_used high water marks in debugfs") Fixes: 02e765697038 ("swiotlb: add debugfs to track swiotlb transient pool usage") Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by: Petr Tesarik <petr.tesarik1@huawei-partners.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
| * | | swiotlb: fix swiotlb_bounce() to do partial sync's correctlyMichael Kelley2024-04-021-17/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In current code, swiotlb_bounce() may do partial sync's correctly in some circumstances, but may incorrectly fail in other circumstances. The failure cases require both of these to be true: 1) swiotlb_align_offset() returns a non-zero "offset" value 2) the tlb_addr of the partial sync area points into the first "offset" bytes of the _second_ or subsequent swiotlb slot allocated for the mapping Code added in commit 868c9ddc182b ("swiotlb: add overflow checks to swiotlb_bounce") attempts to WARN on the invalid case where tlb_addr points into the first "offset" bytes of the _first_ allocated slot. But there's no way for swiotlb_bounce() to distinguish the first slot from the second and subsequent slots, so the WARN can be triggered incorrectly when #2 above is true. Related, current code calculates an adjustment to the orig_addr stored in the swiotlb slot. The adjustment compensates for the difference in the tlb_addr used for the partial sync vs. the tlb_addr for the full mapping. The adjustment is stored in the local variable tlb_offset. But when #1 and #2 above are true, it's valid for this adjustment to be negative. In such case the arithmetic to adjust orig_addr produces the wrong result due to tlb_offset being declared as unsigned. Fix these problems by removing the over-constraining validations added in 868c9ddc182b. Change the declaration of tlb_offset to be signed instead of unsigned so the adjustment arithmetic works correctly. Tested with a test-only hack to how swiotlb_tbl_map_single() calls swiotlb_bounce(). Instead of calling swiotlb_bounce() just once for the entire mapped area, do a loop with each iteration doing only a 128 byte partial sync until the entire mapped area is sync'ed. Then with swiotlb=force on the kernel boot line, run a variety of raw disk writes followed by read and verification of all bytes of the written data. The storage device has DMA min_align_mask set, and the writes are done with a variety of original buffer memory address alignments and overall buffer sizes. For many of the combinations, current code triggers the WARN statements, or the data verification fails. With the fixes, no WARNs occur and all verifications pass. Fixes: 5f89468e2f06 ("swiotlb: manipulate orig_addr when tlb_addr has offset") Fixes: 868c9ddc182b ("swiotlb: add overflow checks to swiotlb_bounce") Signed-off-by: Michael Kelley <mhklinux@outlook.com> Dominique Martinet <dominique.martinet@atmark-techno.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
| * | | swiotlb: extend buffer pre-padding to alloc_align_mask if necessaryPetr Tesarik2024-04-021-13/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow a buffer pre-padding of up to alloc_align_mask, even if it requires allocating additional IO TLB slots. If the allocation alignment is bigger than IO_TLB_SIZE and min_align_mask covers any non-zero bits in the original address between IO_TLB_SIZE and alloc_align_mask, these bits are not preserved in the swiotlb buffer address. To fix this case, increase the allocation size and use a larger offset within the allocated buffer. As a result, extra padding slots may be allocated before the mapping start address. Leave orig_addr in these padding slots initialized to INVALID_PHYS_ADDR. These slots do not correspond to any CPU buffer, so attempts to sync the data should be ignored. The padding slots should be automatically released when the buffer is unmapped. However, swiotlb_tbl_unmap_single() takes only the address of the DMA buffer slot, not the first padding slot. Save the number of padding slots in struct io_tlb_slot and use it to adjust the slot index in swiotlb_release_slots(), so all allocated slots are properly freed. Fixes: 2fd4fa5d3fb5 ("swiotlb: Fix alignment checks when both allocation and DMA masks are present") Link: https://lore.kernel.org/linux-iommu/20240311210507.217daf8b@meshulam.tesarici.cz/ Signed-off-by: Petr Tesarik <petr.tesarik1@huawei-partners.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
* | | | Merge tag 'ata-6.9-rc4' of ↵Linus Torvalds2024-04-133-5/+91
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux Pull ata fixes from Damien Le Moal: - Add the mask_port_map parameter to the ahci driver. This is a follow-up to the recent snafu with the ASMedia controller and its virtual port hidding port-multiplier devices. As ASMedia confirmed that there is no way to determine if these slow-to-probe virtual ports are actually representing the ports of a port-multiplier devices, this new parameter allow masking ports to significantly speed up probing during system boot, resulting in shorter boot times. - A fix for an incorrect handling of a port unlock in ata_scsi_dev_rescan(). - Allow command duration limits to be detected for ACS-4 devices are there are such devices out in the field. * tag 'ata-6.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux: ata: libata-core: Allow command duration limits detection for ACS-4 drives ata: libata-scsi: Fix ata_scsi_dev_rescan() error path ata: ahci: Add mask_port_map module parameter
| * | | | ata: libata-core: Allow command duration limits detection for ACS-4 drivesIgor Pylypiv2024-04-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Even though the command duration limits (CDL) feature was first added in ACS-5 (major version 12), there are some ACS-4 (major version 11) drives that implement CDL as well. IDENTIFY_DEVICE, SUPPORTED_CAPABILITIES, and CURRENT_SETTINGS log pages are mandatory in the ACS-4 standard so it should be safe to read these log pages on older drives implementing the ACS-4 standard. Fixes: 62e4a60e0cdb ("scsi: ata: libata: Detect support for command duration limits") Cc: stable@vger.kernel.org Signed-off-by: Igor Pylypiv <ipylypiv@google.com> Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
| * | | | ata: libata-scsi: Fix ata_scsi_dev_rescan() error pathDamien Le Moal2024-04-131-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 0c76106cb975 ("scsi: sd: Fix TCG OPAL unlock on system resume") incorrectly handles failures of scsi_resume_device() in ata_scsi_dev_rescan(), leading to a double call to spin_unlock_irqrestore() to unlock a device port. Fix this by redefining the goto labels used in case of errors and only unlock the port scsi_scan_mutex when scsi_resume_device() fails. Bug found with the Smatch static checker warning: drivers/ata/libata-scsi.c:4774 ata_scsi_dev_rescan() error: double unlocked 'ap->lock' (orig line 4757) Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Fixes: 0c76106cb975 ("scsi: sd: Fix TCG OPAL unlock on system resume") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Niklas Cassel <cassel@kernel.org>
| * | | | ata: ahci: Add mask_port_map module parameterDamien Le Moal2024-04-051-0/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 0077a504e1a4 ("ahci: asm1166: correct count of reported ports") and 9815e3961754 ("ahci: asm1064: correct count of reported ports") attempted to limit the ports of the ASM1166 and ASM1064 AHCI controllers to avoid long boot times caused by the fact that these adapters report a port map larger than the number of physical ports. The excess ports are "virtual" to hide port multiplier devices and probing these ports takes time. However, these commits caused a regression for users that do use PMP devices, as the ATA devices connected to the PMP cannot be scanned. These commits have thus been reverted by commit 6cd8adc3e18 ("ahci: asm1064: asm1166: don't limit reported ports") to allow the discovery of devices connected through a port multiplier. But this revert re-introduced the long boot times for users that do not use a port multiplier setup. This patch adds the mask_port_map ahci module parameter to allow users to manually specify port map masks for controllers. In the case of the ASMedia 1166 and 1064 controllers, users that do not have port multiplier devices can mask the excess virtual ports exposed by the controller to speedup port scanning, thus reducing boot time. The mask_port_map parameter accepts 2 different formats: - mask_port_map=<mask> This applies the same mask to all AHCI controllers present in the system. This format is convenient for small systems that have only a single AHCI controller. - mask_port_map=<pci_dev>=<mask>,<pci_dev>=mask,... This applies the specified masks only to the PCI device listed. The <pci_dev> field is a regular PCI device ID (domain:bus:dev.func). This ID can be seen following "ahci" in the kernel messages. E.g. for "ahci 0000:01:00.0: 2/2 ports implemented (port mask 0x3)", the <pci_dev> field is "0000:01:00.0". When used, the function ahci_save_initial_config() indicates that a port map mask was applied with the message "masking port_map ...". E.g.: without a mask: modprobe ahci dmesg | grep ahci ... ahci 0000:00:17.0: AHCI vers 0001.0301, 32 command slots, 6 Gbps, SATA mode ahci 0000:00:17.0: (0000:00:17.0) 8/8 ports implemented (port mask 0xff) With a mask: modprobe ahci mask_port_map=0000:00:17.0=0x1 dmesg | grep ahci ... ahci 0000:00:17.0: masking port_map 0xff -> 0x1 ahci 0000:00:17.0: AHCI vers 0001.0301, 32 command slots, 6 Gbps, SATA mode ahci 0000:00:17.0: (0000:00:17.0) 1/8 ports implemented (port mask 0x1) Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Niklas Cassel <cassel@kernel.org>
* | | | | Merge tag 'zonefs-6.9-rc4' of ↵Linus Torvalds2024-04-131-1/+1
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs Pull zonefs fix from Damien Le Moal: - Suppress a coccicheck warning using str_plural() * tag 'zonefs-6.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs: zonefs: Use str_plural() to fix Coccinelle warning