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* | | | | | Merge tag 'nativebhi' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2024-04-0817-43/+317
|\ \ \ \ \ \ | |/ / / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull x86 mitigations from Thomas Gleixner: "Mitigations for the native BHI hardware vulnerabilty: Branch History Injection (BHI) attacks may allow a malicious application to influence indirect branch prediction in kernel by poisoning the branch history. eIBRS isolates indirect branch targets in ring0. The BHB can still influence the choice of indirect branch predictor entry, and although branch predictor entries are isolated between modes when eIBRS is enabled, the BHB itself is not isolated between modes. Add mitigations against it either with the help of microcode or with software sequences for the affected CPUs" [ This also ends up enabling the full mitigation by default despite the system call hardening, because apparently there are other indirect calls that are still sufficiently reachable, and the 'auto' case just isn't hardened enough. We'll have some more inevitable tweaking in the future - Linus ] * tag 'nativebhi' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM: x86: Add BHI_NO x86/bhi: Mitigate KVM by default x86/bhi: Add BHI mitigation knob x86/bhi: Enumerate Branch History Injection (BHI) bug x86/bhi: Define SPEC_CTRL_BHI_DIS_S x86/bhi: Add support for clearing branch history at syscall entry x86/syscall: Don't force use of indirect calls for system calls x86/bugs: Change commas to semicolons in 'spectre_v2' sysfs file
| * | | | | KVM: x86: Add BHI_NODaniel Sneddon2024-04-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel processors that aren't vulnerable to BHI will set MSR_IA32_ARCH_CAPABILITIES[BHI_NO] = 1;. Guests may use this BHI_NO bit to determine if they need to implement BHI mitigations or not. Allow this bit to be passed to the guests. Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/bhi: Mitigate KVM by defaultPawan Gupta2024-04-084-2/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BHI mitigation mode spectre_bhi=auto does not deploy the software mitigation by default. In a cloud environment, it is a likely scenario where userspace is trusted but the guests are not trusted. Deploying system wide mitigation in such cases is not desirable. Update the auto mode to unconditionally mitigate against malicious guests. Deploy the software sequence at VMexit in auto mode also, when hardware mitigation is not available. Unlike the force =on mode, software sequence is not deployed at syscalls in auto mode. Suggested-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/bhi: Add BHI mitigation knobPawan Gupta2024-04-083-1/+115
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Branch history clearing software sequences and hardware control BHI_DIS_S were defined to mitigate Branch History Injection (BHI). Add cmdline spectre_bhi={on|off|auto} to control BHI mitigation: auto - Deploy the hardware mitigation BHI_DIS_S, if available. on - Deploy the hardware mitigation BHI_DIS_S, if available, otherwise deploy the software sequence at syscall entry and VMexit. off - Turn off BHI mitigation. The default is auto mode which does not deploy the software sequence mitigation. This is because of the hardening done in the syscall dispatch path, which is the likely target of BHI. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/bhi: Enumerate Branch History Injection (BHI) bugPawan Gupta2024-04-083-8/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mitigation for BHI is selected based on the bug enumeration. Add bits needed to enumerate BHI bug. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/bhi: Define SPEC_CTRL_BHI_DIS_SDaniel Sneddon2024-04-084-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Newer processors supports a hardware control BHI_DIS_S to mitigate Branch History Injection (BHI). Setting BHI_DIS_S protects the kernel from userspace BHI attacks without having to manually overwrite the branch history. Define MSR_SPEC_CTRL bit BHI_DIS_S and its enumeration CPUID.BHI_CTRL. Mitigation is enabled later. Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/bhi: Add support for clearing branch history at syscall entryPawan Gupta2024-04-087-3/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Branch History Injection (BHI) attacks may allow a malicious application to influence indirect branch prediction in kernel by poisoning the branch history. eIBRS isolates indirect branch targets in ring0. The BHB can still influence the choice of indirect branch predictor entry, and although branch predictor entries are isolated between modes when eIBRS is enabled, the BHB itself is not isolated between modes. Alder Lake and new processors supports a hardware control BHI_DIS_S to mitigate BHI. For older processors Intel has released a software sequence to clear the branch history on parts that don't support BHI_DIS_S. Add support to execute the software sequence at syscall entry and VMexit to overwrite the branch history. For now, branch history is not cleared at interrupt entry, as malicious applications are not believed to have sufficient control over the registers, since previous register state is cleared at interrupt entry. Researchers continue to poke at this area and it may become necessary to clear at interrupt entry as well in the future. This mitigation is only defined here. It is enabled later. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Co-developed-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/syscall: Don't force use of indirect calls for system callsLinus Torvalds2024-04-085-16/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make <asm/syscall.h> build a switch statement instead, and the compiler can either decide to generate an indirect jump, or - more likely these days due to mitigations - just a series of conditional branches. Yes, the conditional branches also have branch prediction, but the branch prediction is much more controlled, in that it just causes speculatively running the wrong system call (harmless), rather than speculatively running possibly wrong random less controlled code gadgets. This doesn't mitigate other indirect calls, but the system call indirection is the first and most easily triggered case. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
| * | | | | x86/bugs: Change commas to semicolons in 'spectre_v2' sysfs fileJosh Poimboeuf2024-04-081-12/+12
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change the format of the 'spectre_v2' vulnerabilities sysfs file slightly by converting the commas to semicolons, so that mitigations for future variants can be grouped together and separated by commas. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | | Merge tag 'x86-urgent-2024-04-07' of ↵Linus Torvalds2024-04-0714-39/+150
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Fix MCE timer reinit locking - Fix/improve CoCo guest random entropy pool init - Fix SEV-SNP late disable bugs - Fix false positive objtool build warning - Fix header dependency bug - Fix resctrl CPU offlining bug * tag 'x86-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunk x86/mce: Make sure to grab mce_sysfs_mutex in set_bank() x86/CPU/AMD: Track SNP host status with cc_platform_*() x86/cc: Add cc_platform_set/_clear() helpers x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORM x86/coco: Require seeding RNG with RDRAND on CoCo systems x86/numa/32: Include missing <asm/pgtable_areas.h> x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offline
| * | | | | x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunkBorislav Petkov (AMD)2024-04-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | srso_alias_untrain_ret() is special code, even if it is a dummy which is called in the !SRSO case, so annotate it like its real counterpart, to address the following objtool splat: vmlinux.o: warning: objtool: .export_symbol+0x2b290: data relocation to !ENDBR: srso_alias_untrain_ret+0x0 Fixes: 4535e1a4174c ("x86/bugs: Fix the SRSO mitigation on Zen3/4") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20240405144637.17908-1-bp@kernel.org
| * | | | | Merge branch 'linus' into x86/urgent, to pick up dependent commitIngo Molnar2024-04-0643-203/+331
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We want to fix: 0e110732473e ("x86/retpoline: Do the necessary fixup to the Zen3/4 srso return thunk for !SRSO") So merge in Linus's latest into x86/urgent to have it available. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | x86/mce: Make sure to grab mce_sysfs_mutex in set_bank()Borislav Petkov (AMD)2024-04-041-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modifying a MCA bank's MCA_CTL bits which control which error types to be reported is done over /sys/devices/system/machinecheck/ ├── machinecheck0 │   ├── bank0 │   ├── bank1 │   ├── bank10 │   ├── bank11 ... sysfs nodes by writing the new bit mask of events to enable. When the write is accepted, the kernel deletes all current timers and reinits all banks. Doing that in parallel can lead to initializing a timer which is already armed and in the timer wheel, i.e., in use already: ODEBUG: init active (active state 0) object: ffff888063a28000 object type: timer_list hint: mce_timer_fn+0x0/0x240 arch/x86/kernel/cpu/mce/core.c:2642 WARNING: CPU: 0 PID: 8120 at lib/debugobjects.c:514 debug_print_object+0x1a0/0x2a0 lib/debugobjects.c:514 Fix that by grabbing the sysfs mutex as the rest of the MCA sysfs code does. Reported by: Yue Sun <samsun1006219@gmail.com> Reported by: xingwei lee <xrivendell7@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/CAEkJfYNiENwQY8yV1LYJ9LjJs%2Bx_-PqMv98gKig55=2vbzffRw@mail.gmail.com
| * | | | | | x86/CPU/AMD: Track SNP host status with cc_platform_*()Borislav Petkov (AMD)2024-04-046-37/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The host SNP worthiness can determined later, after alternatives have been patched, in snp_rmptable_init() depending on cmdline options like iommu=pt which is incompatible with SNP, for example. Which means that one cannot use X86_FEATURE_SEV_SNP and will need to have a special flag for that control. Use that newly added CC_ATTR_HOST_SEV_SNP in the appropriate places. Move kdump_sev_callback() to its rightful place, while at it. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-6-bp@alien8.de
| * | | | | | x86/cc: Add cc_platform_set/_clear() helpersBorislav Petkov (AMD)2024-04-041-0/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add functionality to set and/or clear different attributes of the machine as a confidential computing platform. Add the first one too: whether the machine is running as a host for SEV-SNP guests. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-5-bp@alien8.de
| * | | | | | x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORMBorislav Petkov (AMD)2024-04-041-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The functionality to load SEV-SNP guests by the host will soon rely on cc_platform* helpers because the cpu_feature* API with the early patching is insufficient when SNP support needs to be disabled late. Therefore, pull that functionality in. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-4-bp@alien8.de
| * | | | | | x86/coco: Require seeding RNG with RDRAND on CoCo systemsJason A. Donenfeld2024-04-043-0/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are few uses of CoCo that don't rely on working cryptography and hence a working RNG. Unfortunately, the CoCo threat model means that the VM host cannot be trusted and may actively work against guests to extract secrets or manipulate computation. Since a malicious host can modify or observe nearly all inputs to guests, the only remaining source of entropy for CoCo guests is RDRAND. If RDRAND is broken -- due to CPU hardware fault -- the RNG as a whole is meant to gracefully continue on gathering entropy from other sources, but since there aren't other sources on CoCo, this is catastrophic. This is mostly a concern at boot time when initially seeding the RNG, as after that the consequences of a broken RDRAND are much more theoretical. So, try at boot to seed the RNG using 256 bits of RDRAND output. If this fails, panic(). This will also trigger if the system is booted without RDRAND, as RDRAND is essential for a safe CoCo boot. Add this deliberately to be "just a CoCo x86 driver feature" and not part of the RNG itself. Many device drivers and platforms have some desire to contribute something to the RNG, and add_device_randomness() is specifically meant for this purpose. Any driver can call it with seed data of any quality, or even garbage quality, and it can only possibly make the quality of the RNG better or have no effect, but can never make it worse. Rather than trying to build something into the core of the RNG, consider the particular CoCo issue just a CoCo issue, and therefore separate it all out into driver (well, arch/platform) code. [ bp: Massage commit message. ] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Elena Reshetova <elena.reshetova@intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240326160735.73531-1-Jason@zx2c4.com
| * | | | | | x86/numa/32: Include missing <asm/pgtable_areas.h>Arnd Bergmann2024-04-041-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __vmalloc_start_set declaration is in a header that is not included in numa_32.c in current linux-next: arch/x86/mm/numa_32.c: In function 'initmem_init': arch/x86/mm/numa_32.c:57:9: error: '__vmalloc_start_set' undeclared (first use in this function) 57 | __vmalloc_start_set = true; | ^~~~~~~~~~~~~~~~~~~ arch/x86/mm/numa_32.c:57:9: note: each undeclared identifier is reported only once for each function it appears in Add an explicit #include. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240403202344.3463169-1-arnd@kernel.org
| * | | | | | x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offlineReinette Chatre2024-04-031-1/+2
| | |/ / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tony encountered this OOPS when the last CPU of a domain goes offline while running a kernel built with CONFIG_NO_HZ_FULL: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 Oops: 0000 [#1] PREEMPT SMP NOPTI ... RIP: 0010:__find_nth_andnot_bit+0x66/0x110 ... Call Trace: <TASK> ? __die() ? page_fault_oops() ? exc_page_fault() ? asm_exc_page_fault() cpumask_any_housekeeping() mbm_setup_overflow_handler() resctrl_offline_cpu() resctrl_arch_offline_cpu() cpuhp_invoke_callback() cpuhp_thread_fun() smpboot_thread_fn() kthread() ret_from_fork() ret_from_fork_asm() </TASK> The NULL pointer dereference is encountered while searching for another online CPU in the domain (of which there are none) that can be used to run the MBM overflow handler. Because the kernel is configured with CONFIG_NO_HZ_FULL the search for another CPU (in its effort to prefer those CPUs that aren't marked nohz_full) consults the mask representing the nohz_full CPUs, tick_nohz_full_mask. On a kernel with CONFIG_CPUMASK_OFFSTACK=y tick_nohz_full_mask is not allocated unless the kernel is booted with the "nohz_full=" parameter and because of that any access to tick_nohz_full_mask needs to be guarded with tick_nohz_full_enabled(). Replace the IS_ENABLED(CONFIG_NO_HZ_FULL) with tick_nohz_full_enabled(). The latter ensures tick_nohz_full_mask can be accessed safely and can be used whether kernel is built with CONFIG_NO_HZ_FULL enabled or not. [ Use Ingo's suggestion that combines the two NO_HZ checks into one. ] Fixes: a4846aaf3945 ("x86/resctrl: Add cpumask_any_housekeeping() for limbo/overflow") Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/ff8dfc8d3dcb04b236d523d1e0de13d2ef585223.1711993956.git.reinette.chatre@intel.com Closes: https://lore.kernel.org/lkml/ZgIFT5gZgIQ9A9G7@agluck-desk3/
* | | | | | Merge tag 'timers-urgent-2024-04-07' of ↵Linus Torvalds2024-04-071-2/+1
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "Fix various timer bugs: - Fix a timer migration bug that may result in missed events - Fix timer migration group hierarchy event updates - Fix a PowerPC64 build warning - Fix a handful of DocBook annotation bugs" * tag 'timers-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers/migration: Return early on deactivation timers/migration: Fix ignored event due to missing CPU update vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h timers: Fix text inconsistencies and spelling tick/sched: Fix struct tick_sched doc warnings tick/sched: Fix various kernel-doc warnings timers: Fix kernel-doc format and add Return values time/timekeeping: Fix kernel-doc warnings and typos time/timecounter: Fix inline documentation
| * | | | | | vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.hArnd Bergmann2024-04-031-2/+1
| |/ / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both the vdso rework and the CONFIG_PAGE_SHIFT changes were merged during the v6.9 merge window, so it is now possible to use CONFIG_PAGE_SHIFT instead of including asm/page.h in the vdso. This avoids the workaround for arm64 - commit 8b3843ae3634 ("vdso/datapage: Quick fix - use asm/page-def.h for ARM64") and addresses a build warning for powerpc64: In file included from <built-in>:4: In file included from /home/arnd/arm-soc/arm-soc/lib/vdso/gettimeofday.c:5: In file included from ../include/vdso/datapage.h:25: arch/powerpc/include/asm/page.h:230:9: error: result of comparison of constant 13835058055282163712 with expression of type 'unsigned long' is always true [-Werror,-Wtautological-constant-out-of-range-compare] 230 | return __pa(kaddr) >> PAGE_SHIFT; | ^~~~~~~~~~~ arch/powerpc/include/asm/page.h:217:37: note: expanded from macro '__pa' 217 | VIRTUAL_WARN_ON((unsigned long)(x) < PAGE_OFFSET); \ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~ arch/powerpc/include/asm/page.h:202:73: note: expanded from macro 'VIRTUAL_WARN_ON' 202 | #define VIRTUAL_WARN_ON(x) WARN_ON(IS_ENABLED(CONFIG_DEBUG_VIRTUAL) && (x)) | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~ arch/powerpc/include/asm/bug.h:88:25: note: expanded from macro 'WARN_ON' 88 | int __ret_warn_on = !!(x); \ | ^ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Link: https://lore.kernel.org/r/20240320180228.136371-1-arnd@kernel.org
* | | | | | Merge tag 'perf-urgent-2024-04-07' of ↵Linus Torvalds2024-04-071-4/+4
|\ \ \ \ \ \ | |_|/ / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 perf fix from Ingo Molnar: "Fix a combined PEBS events bug on x86 Intel CPUs" * tag 'perf-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/ds: Don't clear ->pebs_data_cfg for the last PEBS event
| * | | | | perf/x86/intel/ds: Don't clear ->pebs_data_cfg for the last PEBS eventKan Liang2024-04-031-4/+4
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The MSR_PEBS_DATA_CFG MSR register is used to configure which data groups should be generated into a PEBS record, and it's shared among all counters. If there are different configurations among counters, perf combines all the configurations. The first perf command as below requires a complete PEBS record (including memory info, GPRs, XMMs, and LBRs). The second perf command only requires a basic group. However, after the second perf command is running, the MSR_PEBS_DATA_CFG register is cleared. Only a basic group is generated in a PEBS record, which is wrong. The required information for the first perf command is missed. $ perf record --intr-regs=AX,SP,XMM0 -a -C 8 -b -W -d -c 100000003 -o /dev/null -e cpu/event=0xd0,umask=0x81/upp & $ sleep 5 $ perf record --per-thread -c 1 -e cycles:pp --no-timestamp --no-tid taskset -c 8 ./noploop 1000 The first PEBS event is a system-wide PEBS event. The second PEBS event is a per-thread event. When the thread is scheduled out, the intel_pmu_pebs_del() function is invoked to update the PEBS state. Since the system-wide event is still available, the cpuc->n_pebs is 1. The cpuc->pebs_data_cfg is cleared. The data configuration for the system-wide PEBS event is lost. The (cpuc->n_pebs == 1) check was introduced in commit: b6a32f023fcc ("perf/x86: Fix PEBS threshold initialization") At that time, it indeed didn't hurt whether the state was updated during the removal, because only the threshold is updated. The calculation of the threshold takes the last PEBS event into account. However, since commit: b752ea0c28e3 ("perf/x86/intel/ds: Flush PEBS DS when changing PEBS_DATA_CFG") we delay the threshold update, and clear the PEBS data config, which triggers the bug. The PEBS data config update scope should not be shrunk during removal. [ mingo: Improved the changelog & comments. ] Fixes: b752ea0c28e3 ("perf/x86/intel/ds: Flush PEBS DS when changing PEBS_DATA_CFG") Reported-by: Stephane Eranian <eranian@google.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240401133320.703971-1-kan.liang@linux.intel.com
* | | | | Merge tag 'devicetree-fixes-for-6.9-1' of ↵Linus Torvalds2024-04-051-1/+5
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull devicetree fixes from Rob Herring: - Fix NIOS2 boot with external DTB - Add missing synchronization needed between fw_devlink and DT overlay removals - Fix some unit-address regex's to be hex only - Drop some 10+ year old "unstable binding" statements - Add new SoCs to QCom UFS binding - Add TPM bindings to TPM maintainers * tag 'devicetree-fixes-for-6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: nios2: Only use built-in devicetree blob if configured to do so dt-bindings: timer: narrow regex for unit address to hex numbers dt-bindings: soc: fsl: narrow regex for unit address to hex numbers dt-bindings: remoteproc: ti,davinci: remove unstable remark dt-bindings: clock: ti: remove unstable remark dt-bindings: clock: keystone: remove unstable remark of: module: prevent NULL pointer dereference in vsnprintf() dt-bindings: ufs: qcom: document SM6125 UFS dt-bindings: ufs: qcom: document SC7180 UFS dt-bindings: ufs: qcom: document SC8180X UFS of: dynamic: Synchronize of_changeset_destroy() with the devlink removals driver core: Introduce device_link_wait_removal() docs: dt-bindings: add missing address/size-cells to example MAINTAINERS: Add TPM DT bindings to TPM maintainers
| * | | | | nios2: Only use built-in devicetree blob if configured to do soGuenter Roeck2024-04-031-1/+5
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Starting with commit 7b937cc243e5 ("of: Create of_root if no dtb provided by firmware"), attempts to boot nios2 images with an external devicetree blob result in a crash. Kernel panic - not syncing: early_init_dt_alloc_memory_arch: Failed to allocate 72 bytes align=0x40 For nios2, a built-in devicetree blob always overrides devicetree blobs provided by ROMMON/BIOS. This includes the new dummy devicetree blob. Result is that the dummy devicetree blob is used even if an external devicetree blob is provided. Since the dummy devicetree blob does not include any memory information, memory allocations fail, resulting in the crash. To fix the problem, only use the built-in devicetree blob if CONFIG_NIOS2_DTB_SOURCE_BOOL is enabled. Fixes: 7b937cc243e5 ("of: Create of_root if no dtb provided by firmware") Cc: Frank Rowand <frowand.list@gmail.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Rob Herring <robh@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20240322065419.162416-1-linux@roeck-us.net Signed-off-by: Rob Herring <robh@kernel.org>
* | | | | Merge tag 'mm-hotfixes-stable-2024-04-05-11-30' of ↵Linus Torvalds2024-04-051-14/+35
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "8 hotfixes, 3 are cc:stable There are a couple of fixups for this cycle's vmalloc changes and one for the stackdepot changes. And a fix for a very old x86 PAT issue which can cause a warning splat" * tag 'mm-hotfixes-stable-2024-04-05-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: stackdepot: rename pool_index to pool_index_plus_1 x86/mm/pat: fix VM_PAT handling in COW mappings MAINTAINERS: change vmware.com addresses to broadcom.com selftests/mm: include strings.h for ffsl mm: vmalloc: fix lockdep warning mm: vmalloc: bail out early in find_vmap_area() if vmap is not init init: open output files from cpio unpacking with O_LARGEFILE mm/secretmem: fix GUP-fast succeeding on secretmem folios
| * | | | | x86/mm/pat: fix VM_PAT handling in COW mappingsDavid Hildenbrand2024-04-051-14/+35
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PAT handling won't do the right thing in COW mappings: the first PTE (or, in fact, all PTEs) can be replaced during write faults to point at anon folios. Reliably recovering the correct PFN and cachemode using follow_phys() from PTEs will not work in COW mappings. Using follow_phys(), we might just get the address+protection of the anon folio (which is very wrong), or fail on swap/nonswap entries, failing follow_phys() and triggering a WARN_ON_ONCE() in untrack_pfn() and track_pfn_copy(), not properly calling free_pfn_range(). In free_pfn_range(), we either wouldn't call memtype_free() or would call it with the wrong range, possibly leaking memory. To fix that, let's update follow_phys() to refuse returning anon folios, and fallback to using the stored PFN inside vma->vm_pgoff for COW mappings if we run into that. We will now properly handle untrack_pfn() with COW mappings, where we don't need the cachemode. We'll have to fail fork()->track_pfn_copy() if the first page was replaced by an anon folio, though: we'd have to store the cachemode in the VMA to make this work, likely growing the VMA size. For now, lets keep it simple and let track_pfn_copy() just fail in that case: it would have failed in the past with swap/nonswap entries already, and it would have done the wrong thing with anon folios. Simple reproducer to trigger the WARN_ON_ONCE() in untrack_pfn(): <--- C reproducer ---> #include <stdio.h> #include <sys/mman.h> #include <unistd.h> #include <liburing.h> int main(void) { struct io_uring_params p = {}; int ring_fd; size_t size; char *map; ring_fd = io_uring_setup(1, &p); if (ring_fd < 0) { perror("io_uring_setup"); return 1; } size = p.sq_off.array + p.sq_entries * sizeof(unsigned); /* Map the submission queue ring MAP_PRIVATE */ map = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, ring_fd, IORING_OFF_SQ_RING); if (map == MAP_FAILED) { perror("mmap"); return 1; } /* We have at least one page. Let's COW it. */ *map = 0; pause(); return 0; } <--- C reproducer ---> On a system with 16 GiB RAM and swap configured: # ./iouring & # memhog 16G # killall iouring [ 301.552930] ------------[ cut here ]------------ [ 301.553285] WARNING: CPU: 7 PID: 1402 at arch/x86/mm/pat/memtype.c:1060 untrack_pfn+0xf4/0x100 [ 301.553989] Modules linked in: binfmt_misc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_g [ 301.558232] CPU: 7 PID: 1402 Comm: iouring Not tainted 6.7.5-100.fc38.x86_64 #1 [ 301.558772] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebu4 [ 301.559569] RIP: 0010:untrack_pfn+0xf4/0x100 [ 301.559893] Code: 75 c4 eb cf 48 8b 43 10 8b a8 e8 00 00 00 3b 6b 28 74 b8 48 8b 7b 30 e8 ea 1a f7 000 [ 301.561189] RSP: 0018:ffffba2c0377fab8 EFLAGS: 00010282 [ 301.561590] RAX: 00000000ffffffea RBX: ffff9208c8ce9cc0 RCX: 000000010455e047 [ 301.562105] RDX: 07fffffff0eb1e0a RSI: 0000000000000000 RDI: ffff9208c391d200 [ 301.562628] RBP: 0000000000000000 R08: ffffba2c0377fab8 R09: 0000000000000000 [ 301.563145] R10: ffff9208d2292d50 R11: 0000000000000002 R12: 00007fea890e0000 [ 301.563669] R13: 0000000000000000 R14: ffffba2c0377fc08 R15: 0000000000000000 [ 301.564186] FS: 0000000000000000(0000) GS:ffff920c2fbc0000(0000) knlGS:0000000000000000 [ 301.564773] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 301.565197] CR2: 00007fea88ee8a20 CR3: 00000001033a8000 CR4: 0000000000750ef0 [ 301.565725] PKRU: 55555554 [ 301.565944] Call Trace: [ 301.566148] <TASK> [ 301.566325] ? untrack_pfn+0xf4/0x100 [ 301.566618] ? __warn+0x81/0x130 [ 301.566876] ? untrack_pfn+0xf4/0x100 [ 301.567163] ? report_bug+0x171/0x1a0 [ 301.567466] ? handle_bug+0x3c/0x80 [ 301.567743] ? exc_invalid_op+0x17/0x70 [ 301.568038] ? asm_exc_invalid_op+0x1a/0x20 [ 301.568363] ? untrack_pfn+0xf4/0x100 [ 301.568660] ? untrack_pfn+0x65/0x100 [ 301.568947] unmap_single_vma+0xa6/0xe0 [ 301.569247] unmap_vmas+0xb5/0x190 [ 301.569532] exit_mmap+0xec/0x340 [ 301.569801] __mmput+0x3e/0x130 [ 301.570051] do_exit+0x305/0xaf0 ... Link: https://lkml.kernel.org/r/20240403212131.929421-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Wupeng Ma <mawupeng1@huawei.com> Closes: https://lkml.kernel.org/r/20240227122814.3781907-1-mawupeng1@huawei.com Fixes: b1a86e15dc03 ("x86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routines") Fixes: 5899329b1910 ("x86: PAT: implement track/untrack of pfnmap regions for x86 - v3") Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | | | | Merge tag 'arm64-fixes' of ↵Linus Torvalds2024-04-051-4/+1
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fix from Catalin Marinas: "arm64/ptrace fix to use the correct SVE layout based on the saved floating point state rather than the TIF_SVE flag. The latter may be left on during syscalls even if the SVE state is discarded" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64/ptrace: Use saved floating point state type to determine SVE layout
| * | | | | arm64/ptrace: Use saved floating point state type to determine SVE layoutMark Brown2024-04-031-4/+1
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The SVE register sets have two different formats, one of which is a wrapped version of the standard FPSIMD register set and another with actual SVE register data. At present we check TIF_SVE to see if full SVE register state should be provided when reading the SVE regset but if we were in a syscall we may have saved only floating point registers even though that is set. Fix this and simplify the logic by checking and using the format which we recorded when deciding if we should use FPSIMD or SVE format. Fixes: 8c845e273104 ("arm64/sve: Leave SVE enabled on syscall if we don't context switch") Cc: <stable@vger.kernel.org> # 6.2.x Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240325-arm64-ptrace-fp-type-v1-1-8dc846caf11f@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* | | | | Merge tag 'riscv-for-linus-6.9-rc3' of ↵Linus Torvalds2024-04-0512-20/+34
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - A fix for an __{get,put}_kernel_nofault to avoid an uninitialized value causing spurious failures - compat_vdso.so.dbg is now installed to the standard install location - A fix to avoid initializing PERF_SAMPLE_BRANCH_*-related events, as they aren't supported and will just later fail - A fix to make AT_VECTOR_SIZE_ARCH correct now that we're providing AT_MINSIGSTKSZ - pgprot_nx() is now implemented, which fixes vmap W^X protection - A fix for the vector save/restore code, which at least manifests as corrupted vector state when a signal is taken - A fix for a race condition in instruction patching - A fix to avoid leaking the kernel-mode GP to userspace, which is a kernel pointer leak that can be used to defeat KASLR in various ways - A handful of smaller fixes to build warnings, an overzealous printk, and some missing tracing annotations * tag 'riscv-for-linus-6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: process: Fix kernel gp leakage riscv: Disable preemption when using patch_map() riscv: Fix warning by declaring arch_cpu_idle() as noinstr riscv: use KERN_INFO in do_trap riscv: Fix vector state restore in rt_sigreturn() riscv: mm: implement pgprot_nx riscv: compat_vdso: align VDSOAS build log RISC-V: Update AT_VECTOR_SIZE_ARCH for new AT_MINSIGSTKSZ riscv: Mark __se_sys_* functions __used drivers/perf: riscv: Disable PERF_SAMPLE_BRANCH_* while not supported riscv: compat_vdso: install compat_vdso.so.dbg to /lib/modules/*/vdso/ riscv: hwprobe: do not produce frtace relocation riscv: Fix spurious errors from __get/put_kernel_nofault riscv: mm: Fix prototype to avoid discarding const
| * | | | | riscv: process: Fix kernel gp leakageStefan O'Rear2024-04-041-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | childregs represents the registers which are active for the new thread in user context. For a kernel thread, childregs->gp is never used since the kernel gp is not touched by switch_to. For a user mode helper, the gp value can be observed in user space after execve or possibly by other means. [From the email thread] The /* Kernel thread */ comment is somewhat inaccurate in that it is also used for user_mode_helper threads, which exec a user process, e.g. /sbin/init or when /proc/sys/kernel/core_pattern is a pipe. Such threads do not have PF_KTHREAD set and are valid targets for ptrace etc. even before they exec. childregs is the *user* context during syscall execution and it is observable from userspace in at least five ways: 1. kernel_execve does not currently clear integer registers, so the starting register state for PID 1 and other user processes started by the kernel has sp = user stack, gp = kernel __global_pointer$, all other integer registers zeroed by the memset in the patch comment. This is a bug in its own right, but I'm unwilling to bet that it is the only way to exploit the issue addressed by this patch. 2. ptrace(PTRACE_GETREGSET): you can PTRACE_ATTACH to a user_mode_helper thread before it execs, but ptrace requires SIGSTOP to be delivered which can only happen at user/kernel boundaries. 3. /proc/*/task/*/syscall: this is perfectly happy to read pt_regs for user_mode_helpers before the exec completes, but gp is not one of the registers it returns. 4. PERF_SAMPLE_REGS_USER: LOCKDOWN_PERF normally prevents access to kernel addresses via PERF_SAMPLE_REGS_INTR, but due to this bug kernel addresses are also exposed via PERF_SAMPLE_REGS_USER which is permitted under LOCKDOWN_PERF. I have not attempted to write exploit code. 5. Much of the tracing infrastructure allows access to user registers. I have not attempted to determine which forms of tracing allow access to user registers without already allowing access to kernel registers. Fixes: 7db91e57a0ac ("RISC-V: Task implementation") Cc: stable@vger.kernel.org Signed-off-by: Stefan O'Rear <sorear@fastmail.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240327061258.2370291-1-sorear@fastmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: Disable preemption when using patch_map()Alexandre Ghiti2024-04-041-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | patch_map() uses fixmap mappings to circumvent the non-writability of the kernel text mapping. The __set_fixmap() function only flushes the current cpu tlb, it does not emit an IPI so we must make sure that while we use a fixmap mapping, the current task is not migrated on another cpu which could miss the newly introduced fixmap mapping. So in order to avoid any task migration, disable the preemption. Reported-by: Andrea Parri <andrea@rivosinc.com> Closes: https://lore.kernel.org/all/ZcS+GAaM25LXsBOl@andrea/ Reported-by: Andy Chiu <andy.chiu@sifive.com> Closes: https://lore.kernel.org/linux-riscv/CABgGipUMz3Sffu-CkmeUB1dKVwVQ73+7=sgC45-m0AE9RCjOZg@mail.gmail.com/ Fixes: cad539baa48f ("riscv: implement a memset like function for text") Fixes: 0ff7c3b33127 ("riscv: Use text_mutex instead of patch_lock") Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Acked-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20240326203017.310422-3-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: Fix warning by declaring arch_cpu_idle() as noinstrAlexandre Ghiti2024-04-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following warning appears when using ftrace: [89855.443413] RCU not on for: arch_cpu_idle+0x0/0x1c [89855.445640] WARNING: CPU: 5 PID: 0 at include/linux/trace_recursion.h:162 arch_ftrace_ops_list_func+0x208/0x228 [89855.445824] Modules linked in: xt_conntrack(E) nft_chain_nat(E) xt_MASQUERADE(E) nf_conntrack_netlink(E) xt_addrtype(E) nft_compat(E) nf_tables(E) nfnetlink(E) br_netfilter(E) cfg80211(E) nls_iso8859_1(E) ofpart(E) redboot(E) cmdlinepart(E) cfi_cmdset_0001(E) virtio_net(E) cfi_probe(E) cfi_util(E) 9pnet_virtio(E) gen_probe(E) net_failover(E) virtio_rng(E) failover(E) 9pnet(E) physmap(E) map_funcs(E) chipreg(E) mtd(E) uio_pdrv_genirq(E) uio(E) dm_multipath(E) scsi_dh_rdac(E) scsi_dh_emc(E) scsi_dh_alua(E) drm(E) efi_pstore(E) backlight(E) ip_tables(E) x_tables(E) raid10(E) raid456(E) async_raid6_recov(E) async_memcpy(E) async_pq(E) async_xor(E) xor(E) async_tx(E) raid6_pq(E) raid1(E) raid0(E) virtio_blk(E) [89855.451563] CPU: 5 PID: 0 Comm: swapper/5 Tainted: G E 6.8.0-rc6ubuntu-defconfig #2 [89855.451726] Hardware name: riscv-virtio,qemu (DT) [89855.451899] epc : arch_ftrace_ops_list_func+0x208/0x228 [89855.452016] ra : arch_ftrace_ops_list_func+0x208/0x228 [89855.452119] epc : ffffffff8016b216 ra : ffffffff8016b216 sp : ffffaf808090fdb0 [89855.452171] gp : ffffffff827c7680 tp : ffffaf808089ad40 t0 : ffffffff800c0dd8 [89855.452216] t1 : 0000000000000001 t2 : 0000000000000000 s0 : ffffaf808090fe30 [89855.452306] s1 : 0000000000000000 a0 : 0000000000000026 a1 : ffffffff82cd6ac8 [89855.452423] a2 : ffffffff800458c8 a3 : ffffaf80b1870640 a4 : 0000000000000000 [89855.452646] a5 : 0000000000000000 a6 : 00000000ffffffff a7 : ffffffffffffffff [89855.452698] s2 : ffffffff82766872 s3 : ffffffff80004caa s4 : ffffffff80ebea90 [89855.452743] s5 : ffffaf808089bd40 s6 : 8000000a00006e00 s7 : 0000000000000008 [89855.452787] s8 : 0000000000002000 s9 : 0000000080043700 s10: 0000000000000000 [89855.452831] s11: 0000000000000000 t3 : 0000000000100000 t4 : 0000000000000064 [89855.452874] t5 : 000000000000000c t6 : ffffaf80b182dbfc [89855.452929] status: 0000000200000100 badaddr: 0000000000000000 cause: 0000000000000003 [89855.453053] [<ffffffff8016b216>] arch_ftrace_ops_list_func+0x208/0x228 [89855.453191] [<ffffffff8000e082>] ftrace_call+0x8/0x22 [89855.453265] [<ffffffff800a149c>] do_idle+0x24c/0x2ca [89855.453357] [<ffffffff8000da54>] return_to_handler+0x0/0x26 [89855.453429] [<ffffffff8000b716>] smp_callin+0x92/0xb6 [89855.453785] ---[ end trace 0000000000000000 ]--- To fix this, mark arch_cpu_idle() as noinstr, like it is done in commit a9cbc1b471d2 ("s390/idle: mark arch_cpu_idle() noinstr"). Reported-by: Evgenii Shatokhin <e.shatokhin@yadro.com> Closes: https://lore.kernel.org/linux-riscv/51f21b87-ebed-4411-afbc-c00d3dea2bab@yadro.com/ Fixes: cfbc4f81c9d0 ("riscv: Select ARCH_WANTS_NO_INSTR") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Andy Chiu <andy.chiu@sifive.com> Tested-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20240326203017.310422-2-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: use KERN_INFO in do_trapAndreas Schwab2024-04-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Print the instruction dump with info instead of emergency level. The unhandled signal message is only for informational purpose. Fixes: b8a03a634129 ("riscv: add userland instruction dump to RISC-V splats") Signed-off-by: Andreas Schwab <schwab@suse.de> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Yunhui Cui <cuiyunhui@bytedance.com> Link: https://lore.kernel.org/r/mvmy1aegrhm.fsf@suse.de Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: Fix vector state restore in rt_sigreturn()Björn Töpel2024-04-031-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The RISC-V Vector specification states in "Appendix D: Calling Convention for Vector State" [1] that "Executing a system call causes all caller-saved vector registers (v0-v31, vl, vtype) and vstart to become unspecified.". In the RISC-V kernel this is called "discarding the vstate". Returning from a signal handler via the rt_sigreturn() syscall, vector discard is also performed. However, this is not an issue since the vector state should be restored from the sigcontext, and therefore not care about the vector discard. The "live state" is the actual vector register in the running context, and the "vstate" is the vector state of the task. A dirty live state, means that the vstate and live state are not in synch. When vectorized user_from_copy() was introduced, an bug sneaked in at the restoration code, related to the discard of the live state. An example when this go wrong: 1. A userland application is executing vector code 2. The application receives a signal, and the signal handler is entered. 3. The application returns from the signal handler, using the rt_sigreturn() syscall. 4. The live vector state is discarded upon entering the rt_sigreturn(), and the live state is marked as "dirty", indicating that the live state need to be synchronized with the current vstate. 5. rt_sigreturn() restores the vstate, except the Vector registers, from the sigcontext 6. rt_sigreturn() restores the Vector registers, from the sigcontext, and now the vectorized user_from_copy() is used. The dirty live state from the discard is saved to the vstate, making the vstate corrupt. 7. rt_sigreturn() returns to the application, which crashes due to corrupted vstate. Note that the vectorized user_from_copy() is invoked depending on the value of CONFIG_RISCV_ISA_V_UCOPY_THRESHOLD. Default is 768, which means that vlen has to be larger than 128b for this bug to trigger. The fix is simply to mark the live state as non-dirty/clean prior performing the vstate restore. Link: https://github.com/riscv/riscv-isa-manual/releases/download/riscv-isa-release-8abdb41-2024-03-26/unpriv-isa-asciidoc.pdf # [1] Reported-by: Charlie Jenkins <charlie@rivosinc.com> Reported-by: Vineet Gupta <vgupta@kernel.org> Fixes: c2a658d41924 ("riscv: lib: vectorize copy_to_user/copy_from_user") Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Andy Chiu <andy.chiu@sifive.com> Tested-by: Vineet Gupta <vineetg@rivosinc.com> Link: https://lore.kernel.org/r/20240403072638.567446-1-bjorn@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: mm: implement pgprot_nxJisheng Zhang2024-03-271-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit cca98e9f8b5e ("mm: enforce that vmap can't map pages executable") enforces the W^X protection by not allowing remapping existing pages as executable. Add riscv bits so that riscv can benefit the same protection. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Samuel Holland <samuel.holland@sifive.com> Tested-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20231121160637.3856-1-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: compat_vdso: align VDSOAS build logMasahiro Yamada2024-03-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add one more space after "VDSOAS" for better alignment in the build log. [Before] LDS arch/riscv/kernel/compat_vdso/compat_vdso.lds VDSOAS arch/riscv/kernel/compat_vdso/rt_sigreturn.o VDSOAS arch/riscv/kernel/compat_vdso/getcpu.o VDSOAS arch/riscv/kernel/compat_vdso/flush_icache.o VDSOAS arch/riscv/kernel/compat_vdso/note.o VDSOLD arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg VDSOSYM include/generated/compat_vdso-offsets.h [After] LDS arch/riscv/kernel/compat_vdso/compat_vdso.lds VDSOAS arch/riscv/kernel/compat_vdso/rt_sigreturn.o VDSOAS arch/riscv/kernel/compat_vdso/getcpu.o VDSOAS arch/riscv/kernel/compat_vdso/flush_icache.o VDSOAS arch/riscv/kernel/compat_vdso/note.o VDSOLD arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg VDSOSYM include/generated/compat_vdso-offsets.h Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20231117125843.1058553-1-masahiroy@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | RISC-V: Update AT_VECTOR_SIZE_ARCH for new AT_MINSIGSTKSZVictor Isaev2024-03-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "riscv: signal: Report signal frame size to userspace via auxv" (e92f469) has added new constant AT_MINSIGSTKSZ but failed to increment the size of auxv, keeping AT_VECTOR_SIZE_ARCH at 9. This fix correctly increments AT_VECTOR_SIZE_ARCH to 10, following the approach in the commit 94b07c1 ("arm64: signal: Report signal frame size to userspace via auxv"). Link: https://lore.kernel.org/r/73883406.20231215232720@torrio.net Link: https://lore.kernel.org/all/20240102133617.3649-1-victor@torrio.net/ Reported-by: Ivan Komarov <ivan.komarov@dfyz.info> Closes: https://lore.kernel.org/linux-riscv/CY3Z02NYV1C4.11BLB9PLVW9G1@fedora/ Fixes: e92f469b0771 ("riscv: signal: Report signal frame size to userspace via auxv") Signed-off-by: Victor Isaev <isv@google.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: Mark __se_sys_* functions __usedSami Tolvanen2024-03-261-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clang doesn't think ___se_sys_* functions used even though they are aliased to __se_sys_*, resulting in -Wunused-function warnings when building rv32. For example: mm/oom_kill.c:1195:1: warning: unused function '___se_sys_process_mrelease' [-Wunused-function] 1195 | SYSCALL_DEFINE2(process_mrelease, int, pidfd, unsigned int, flags) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/syscalls.h:221:36: note: expanded from macro 'SYSCALL_DEFINE2' 221 | #define SYSCALL_DEFINE2(name, ...) SYSCALL_DEFINEx(2, _##name, __VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/syscalls.h:231:2: note: expanded from macro 'SYSCALL_DEFINEx' 231 | __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/riscv/include/asm/syscall_wrapper.h:81:2: note: expanded from macro '__SYSCALL_DEFINEx' 81 | __SYSCALL_SE_DEFINEx(x, sys, name, __VA_ARGS__) \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/riscv/include/asm/syscall_wrapper.h:40:14: note: expanded from macro '__SYSCALL_SE_DEFINEx' 40 | static long ___se_##prefix##name(__MAP(x,__SC_LONG,__VA_ARGS__)) | ^~~~~~~~~~~~~~~~~~~~ <scratch space>:30:1: note: expanded from here 30 | ___se_sys_process_mrelease | ^~~~~~~~~~~~~~~~~~~~~~~~~~ 1 warning generated. Mark the functions __used explicitly to fix the Clang warnings. Fixes: a9ad73295cc1 ("riscv: Fix syscall wrapper for >word-size arguments") Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Tested-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20240326153712.1839482-2-samitolvanen@google.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: compat_vdso: install compat_vdso.so.dbg to /lib/modules/*/vdso/Masahiro Yamada2024-03-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'make vdso_install' installs debug vdso files to /lib/modules/*/vdso/. Only for the compat vdso on riscv, the installation destination differs; compat_vdso.so.dbg is installed to /lib/module/*/compat_vdso/. To follow the standard install destination and simplify the vdso_install logic, change the install destination to standard /lib/modules/*/vdso/. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20231117125807.1058477-1-masahiroy@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: hwprobe: do not produce frtace relocationVladimir Isaev2024-03-261-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Such relocation causes crash of android linker similar to one described in commit e05d57dcb8c7 ("riscv: Fixup __vdso_gettimeofday broke dynamic ftrace"). Looks like this relocation is added by CONFIG_DYNAMIC_FTRACE which is disabled in the default android kernel. Before: readelf -rW arch/riscv/kernel/vdso/vdso.so: Relocation section '.rela.dyn' at offset 0xd00 contains 1 entry: Offset Info Type 0000000000000d20 0000000000000003 R_RISCV_RELATIVE objdump: 0000000000000c86 <__vdso_riscv_hwprobe@@LINUX_4.15>: c86: 0001 nop c88: 0001 nop c8a: 0001 nop c8c: 0001 nop c8e: e211 bnez a2,c92 <__vdso_riscv_hwprobe... After: readelf -rW arch/riscv/kernel/vdso/vdso.so: There are no relocations in this file. objdump: 0000000000000c86 <__vdso_riscv_hwprobe@@LINUX_4.15>: c86: e211 bnez a2,c8a <__vdso_riscv_hwprobe... c88: c6b9 beqz a3,cd6 <__vdso_riscv_hwprobe... c8a: e739 bnez a4,cd8 <__vdso_riscv_hwprobe... c8c: ffffd797 auipc a5,0xffffd Also disable SCS since it also should not be available in vdso. Fixes: aa5af0aa90ba ("RISC-V: Add hwprobe vDSO function and data") Signed-off-by: Roman Artemev <roman.artemev@syntacore.com> Signed-off-by: Vladimir Isaev <vladimir.isaev@syntacore.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Guo Ren <guoren@kernel.org> Link: https://lore.kernel.org/r/20240313085843.17661-1-vladimir.isaev@syntacore.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: Fix spurious errors from __get/put_kernel_nofaultSamuel Holland2024-03-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These macros did not initialize __kr_err, so they could fail even if the access did not fault. Cc: stable@vger.kernel.org Fixes: d464118cdc41 ("riscv: implement __get_kernel_nofault and __put_user_nofault") Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240312022030.320789-1-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | | | | riscv: mm: Fix prototype to avoid discarding constSamuel Holland2024-03-261-2/+2
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __flush_tlb_range() does not modify the provided cpumask, so its cmask parameter can be pointer-to-const. This avoids the unsafe cast of cpu_online_mask. Fixes: 54d7431af73e ("riscv: Add support for BATCHED_UNMAP_TLB_FLUSH") Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240301201837.2826172-1-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* | | | | Merge tag 's390-6.9-3' of ↵Linus Torvalds2024-04-057-58/+67
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Alexander Gordeev: - Fix missing NULL pointer check when determining guest/host fault - Mark all functions in asm/atomic_ops.h, asm/atomic.h and asm/preempt.h as __always_inline to avoid unwanted instrumentation - Fix removal of a Processor Activity Instrumentation (PAI) sampling event in PMU device driver - Align system call table on 8 bytes * tag 's390-6.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/entry: align system call table on 8 bytes s390/pai: fix sampling event removal for PMU device driver s390/preempt: mark all functions __always_inline s390/atomic: mark all functions __always_inline s390/mm: fix NULL pointer dereference
| * | | | | s390/entry: align system call table on 8 bytesSumanth Korikkar2024-04-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Align system call table on 8 bytes. With sys_call_table entry size of 8 bytes that eliminates the possibility of a system call pointer crossing cache line boundary. Cc: stable@kernel.org Suggested-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | | | s390/pai: fix sampling event removal for PMU device driverThomas Richter2024-04-032-6/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case of a sampling event, the PAI PMU device drivers need a reference to this event. Currently to PMU device driver reference is removed when a sampling event is destroyed. This may lead to situations where the reference of the PMU device driver is removed while being used by a different sampling event. Reset the event reference pointer of the PMU device driver when a sampling event is deleted and before the next one might be added. Fixes: 39d62336f5c1 ("s390/pai: add support for cryptography counters") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | | | s390/preempt: mark all functions __always_inlineIlya Leoshkevich2024-04-031-18/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | preempt_count-related functions are quite ubiquitous and may be called by noinstr ones, introducing unwanted instrumentation. Here is one example call chain: irqentry_nmi_enter() # noinstr lockdep_hardirqs_enabled() this_cpu_read() __pcpu_size_call_return() this_cpu_read_*() this_cpu_generic_read() __this_cpu_generic_read_nopreempt() preempt_disable_notrace() __preempt_count_inc() __preempt_count_add() They are very small, so there are no significant downsides to force-inlining them. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/r/20240320230007.4782-3-iii@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | | | s390/atomic: mark all functions __always_inlineIlya Leoshkevich2024-04-032-33/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Atomic functions are quite ubiquitous and may be called by noinstr ones, introducing unwanted instrumentation. They are very small, so there are no significant downsides to force-inlining them. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/r/20240320230007.4782-2-iii@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | | | s390/mm: fix NULL pointer dereferenceHeiko Carstens2024-04-031-1/+1
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The recently added check to figure out if a fault happened on gmap ASCE dereferences the gmap pointer in lowcore without checking that it is not NULL. For all non-KVM processes the pointer is NULL, so that some value from lowcore will be read. With the current layouts of struct gmap and struct lowcore the read value (aka ASCE) is zero, so that this doesn't lead to any observable bug; at least currently. Fix this by adding the missing NULL pointer check. Fixes: 64c3431808bd ("s390/entry: compare gmap asce to determine guest/host fault") Acked-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* | | | | x86/cpufeatures: Add CPUID_LNX_5 to track recently added Linux-defined wordSean Christopherson2024-04-042-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add CPUID_LNX_5 to track cpufeatures' word 21, and add the appropriate compile-time assert in KVM to prevent direct lookups on the features in CPUID_LNX_5. KVM uses X86_FEATURE_* flags to manage guest CPUID, and so must translate features that are scattered by Linux from the Linux-defined bit to the hardware-defined bit, i.e. should never try to directly access scattered features in guest CPUID. Opportunistically add NR_CPUID_WORDS to enum cpuid_leafs, along with a compile-time assert in KVM's CPUID infrastructure to ensure that future additions update cpuid_leafs along with NCAPINTS. No functional change intended. Fixes: 7f274e609f3d ("x86/cpufeatures: Add new word for scattered features") Cc: Sandipan Das <sandipan.das@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>