summaryrefslogtreecommitdiff
path: root/arch
AgeCommit message (Collapse)Author
2024-02-20mips: txx9: make txx9_sramc_subsys constRicardo B. Marliere
Now that the driver core can properly handle constant struct bus_type, move the txx9_sramc_subsys variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20mips: sgi-ip22: make gio_bus_type constRicardo B. Marliere
Now that the driver core can properly handle constant struct bus_type, move the gio_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: move unselectable entries out of the "CPU type" choiceMasahiro Yamada
Move the following entries out of the "CPU type" choice: - LOONGSON3_ENHANCEMENT - CPU_LOONGSON3_WORKAROUNDS - CPU_LOONGSON3_CPUCFG_EMULATION These entries cannot be selected from the choice because they depend on CPU_LOONGSON64, which is also located in the same choice. In fact, Kconfig does not consider them as choice values because they become children of CPU_LOOONGSON64 due to the automatic submenu creation in menu_finalize(). However, it is hard to understand this behavior unless you are familiar with the Kconfig internals. "choice" should contain only selectable entries. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: Alchemy: Use kcalloc() instead of kzalloc()Erick Archer
As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, use the purpose specific kcalloc() function instead of the argument size * count in the kzalloc() function. Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] Link: https://github.com/KSPP/linux/issues/162 Signed-off-by: Erick Archer <erick.archer@gmx.com> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: Add support for Mobileye EyeQ5Gregory CLEMENT
Introduce support for the MIPS based Mobileye EyeQ5 SoCs. Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: Share generic kernel code with other architectureGregory CLEMENT
Some architectures might seek to utilize a significant portion of the generic kernel code while maintaining independence from the generic kernel due to specific peculiarities. This patch allows for the reuse of core code, preventing unnecessary duplication. Suggested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20x86/vdso: Fix rethunk patching for vdso-image-{32,64}.oJosh Poimboeuf
For CONFIG_RETHUNK kernels, objtool annotates all the function return sites so they can be patched during boot. By design, after apply_returns() is called, all tail-calls to the compiler-generated default return thunk (__x86_return_thunk) should be patched out and replaced with whatever's needed for any mitigations (or lack thereof). The commit 4461438a8405 ("x86/retpoline: Ensure default return thunk isn't used at runtime") adds a runtime check and a WARN_ONCE() if the default return thunk ever gets executed after alternatives have been applied. This warning is a sanity check to make sure objtool and apply_returns() are doing their job. As Nathan reported, that check found something: Unpatched return thunk in use. This should not happen! WARNING: CPU: 0 PID: 1 at arch/x86/kernel/cpu/bugs.c:2856 __warn_thunk+0x27/0x40 RIP: 0010:__warn_thunk+0x27/0x40 Call Trace: <TASK> ? show_regs ? __warn ? __warn_thunk ? report_bug ? console_unlock ? handle_bug ? exc_invalid_op ? asm_exc_invalid_op ? ia32_binfmt_init ? __warn_thunk warn_thunk_thunk do_one_initcall kernel_init_freeable ? __pfx_kernel_init kernel_init ret_from_fork ? __pfx_kernel_init ret_from_fork_asm </TASK> Boris debugged to find that the unpatched return site was in init_vdso_image_64(), and its translation unit wasn't being analyzed by objtool, so it never got annotated. So it got ignored by apply_returns(). This is only a minor issue, as this function is only called during boot. Still, objtool needs full visibility to the kernel. Fix it by enabling objtool on vdso-image-{32,64}.o. Note this problem can only be seen with !CONFIG_X86_KERNEL_IBT, as that requires objtool to run individually on all translation units rather on vmlinux.o. [ bp: Massage commit message. ] Reported-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240215032049.GA3944823@dev-arch.thelio-3990X
2024-02-20arm64/sme: Restore SMCR_EL1.EZT0 on exit from suspendMark Brown
The fields in SMCR_EL1 reset to an architecturally UNKNOWN value. Since we do not otherwise manage the traps configured in this register at runtime we need to reconfigure them after a suspend in case nothing else was kind enough to preserve them for us. Do so for SMCR_EL1.EZT0. Fixes: d4913eee152d ("arm64/sme: Add basic enumeration for SME2") Reported-by: Jackson Cooper-Driver <Jackson.Cooper-Driver@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240213-arm64-sme-resume-v3-2-17e05e493471@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2024-02-20arm64/sme: Restore SME registers on exit from suspendMark Brown
The fields in SMCR_EL1 and SMPRI_EL1 reset to an architecturally UNKNOWN value. Since we do not otherwise manage the traps configured in this register at runtime we need to reconfigure them after a suspend in case nothing else was kind enough to preserve them for us. The vector length will be restored as part of restoring the SME state for the next SME using task. Fixes: a1f4ccd25cc2 ("arm64/sme: Provide Kconfig for SME") Reported-by: Jackson Cooper-Driver <Jackson.Cooper-Driver@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240213-arm64-sme-resume-v3-1-17e05e493471@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2024-02-20Revert "arm64: jump_label: use constraints "Si" instead of "i""Will Deacon
This reverts commit f9daab0ad01cf9d165dbbbf106ca4e61d06e7fe8. Geert reports that his particular GCC 5.5 vintage toolchain fails to build an arm64 defconfig because of this change: | arch/arm64/include/asm/jump_label.h:25:2: error: invalid 'asm': | invalid operand | asm goto( ^ Aopparently, this is something we claim to support, so let's revert back to the old jump label constraint for now while discussions about raising the minimum GCC version are ongoing. Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/CAMuHMdX+6fnAf8Hm6EqYJPAjrrLO9T7c=Gu3S8V_pqjSDowJ6g@mail.gmail.com Signed-off-by: Will Deacon <will@kernel.org>
2024-02-20hexagon: select GENERIC_IRQ_PROBE instead of redefining itMasahiro Yamada
Select GENERIC_IRQ_PROBE, as the other architectures do. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Brian Cain <bcain@quicinc.com>
2024-02-20hexagon: select FRAME_POINTER instead of redefining itMasahiro Yamada
Because FRAME_POINTER is defined in lib/Kconfig.debug, the arch Kconfig should select it. Add 'select FRAME_POINTER' to HEXAGON. ARCH_WANT_FRAME_POINTERS must also be selected to avoid the unmet dependency warning. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Brian Cain <bcain@quicinc.com>
2024-02-20treewide: replace or remove redundant def_bool in Kconfig filesMasahiro Yamada
'def_bool X' is a shorthand for 'bool' plus 'default X'. 'def_bool' is redundant where 'bool' is already present, so 'def_bool X' can be replaced with 'default X', or removed if X is 'n'. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-02-20MIPS: mobileye: Add EPM5 device treeGregory CLEMENT
Add a device tree for the Mobileye EPM5 evaluation board. Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: mobileye: Add EyeQ5 dtsiGregory CLEMENT
Add a device tree include file for the Mobileye EyeQ5 SoC. Based on the work of Slava Samsonov <stanislav.samsonov@intel.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: cps-vec: Use macros for 64bits accessGregory CLEMENT
Some access are 32 bits only while they seems better to be done in 64bis for 64 bit kernel. This was extract from an initial patch from Jiaxun Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: traps: Give more explanations if ebase doesn't belong to KSEG0Gregory CLEMENT
With the expanded support for placing the kernel in XPHYS rather than just KSEG0, scenarios where ebase doesn't belong to KSEG0 are more likely to occur. In such cases, we currently experience a substantial and perplexing stack dump without any accompanying explanation. To rectify this, we aim to replace the uninformative stack dump with a warning that offers a clear explanation of the issue. Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: Allows relocation exception vectors everywhereJiaxun Yang
Now the exception vector for CPS systems are allocated on-fly with memblock as well. It will try to allocate from KSEG1 first, and then try to allocate in low 4G if possible. The main reset vector is now generated by uasm, to avoid tons of patches to the code. Other vectors are copied to the location later. move 64bits fix in an other patch fix cache issue with mips_cps_core_entry rewrite the patch to reduce the diff stat move extern in header use cache address for copying vector gc: use the new macro CKSEG[0A1]DDR_OR_64BIT() Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: Fix set_uncached_handler for ebase in XKPHYSJiaxun Yang
ebase might reside in XKPHYS if memblock is unable to allocate memory within the KSEG0 physical range. To map EBASE into uncached space, we convert it back to its physical address and utilize the new CKSEG1ADDR_OR_64BIT helper for mapping. Co-developed-by: Vladimir Kondratiev <vladimir.kondratiev@intel.com> Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@intel.com> Co-developed-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: spaces: Define a couple of handy macrosGregory CLEMENT
Define CKSEGX_SIZE to represent the size of each KSEG segment. Introduce CKSEG0ADDR_OR_64BIT and CKSEG1ADDR_OR_64BIT to get an XPHYS address in 64bits and CKSEG[01]ADDR() in 32 bits mode. Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: pm-cps: Use GPR number macrosJiaxun Yang
Use GPR number macros in uasm code generation parts to reduce code duplication. There are functional change due to difference in register symbolic names between OABI and NABI, while existing code is only using definitions from OABI. Code pieces are carefully inspected to ensure register usages are safe on NABI as well. We changed register allocation of r_pcohctl from T7 to T8 as T7 is not available on NABI and we just want a caller saved scratch register here. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: kvm/entry: Use GPR number macrosJiaxun Yang
Use GPR number macros in uasm code generation parts to reduce code duplication. No functional change. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: tlbex: Use GPR number macrosJiaxun Yang
Use GPR number macros in uasm code generation parts to reduce code duplication. No functional change. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: page: Use GPR number macrosJiaxun Yang
Use GPR number macros in uasm code generation parts to reduce code duplication. No functional change. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: traps: Use GPR number macrosJiaxun Yang
Use GPR number macros in uasm code generation parts to reduce code duplication. No functional change. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: regdefs.h: Define a set of register numbersJiaxun Yang
Define a set of register numbers with their symbolic names to help with uasm code. All names are prefixed by GPR_ to prevent naming clash. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: regdefs.h: Guard all defines with __ASSEMBLY__Jiaxun Yang
Those definitions are only meant to be used in pure assembly code. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20MIPS: Unify define of CP0 registers for uasm codeJiaxun Yang
Definitions of uasm variant of CP0 registers are unified to mipsregs.h, so they lay together with uasm variant of the code. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2024-02-20KVM: PPC: Book3S HV: Fix L2 guest reboot failure due to empty 'arch_compat'Amit Machhiwal
Currently, rebooting a pseries nested qemu-kvm guest (L2) results in below error as L1 qemu sends PVR value 'arch_compat' == 0 via ppc_set_compat ioctl. This triggers a condition failure in kvmppc_set_arch_compat() resulting in an EINVAL. qemu-system-ppc64: Unable to set CPU compatibility mode in KVM: Invalid argument Also, a value of 0 for arch_compat generally refers the default compatibility of the host. But, arch_compat, being a Guest Wide Element in nested API v2, cannot be set to 0 in GSB as PowerVM (L0) expects a non-zero value. A value of 0 triggers a kernel trap during a reboot and consequently causes it to fail: [ 22.106360] reboot: Restarting system KVM: unknown exit, hardware reason ffffffffffffffea NIP 0000000000000100 LR 000000000000fe44 CTR 0000000000000000 XER 0000000020040092 CPU#0 MSR 0000000000001000 HID0 0000000000000000 HF 6c000000 iidx 3 didx 3 TB 00000000 00000000 DECR 0 GPR00 0000000000000000 0000000000000000 c000000002a8c300 000000007fe00000 GPR04 0000000000000000 0000000000000000 0000000000001002 8000000002803033 GPR08 000000000a000000 0000000000000000 0000000000000004 000000002fff0000 GPR12 0000000000000000 c000000002e10000 0000000105639200 0000000000000004 GPR16 0000000000000000 000000010563a090 0000000000000000 0000000000000000 GPR20 0000000105639e20 00000001056399c8 00007fffe54abab0 0000000105639288 GPR24 0000000000000000 0000000000000001 0000000000000001 0000000000000000 GPR28 0000000000000000 0000000000000000 c000000002b30840 0000000000000000 CR 00000000 [ - - - - - - - - ] RES 000@ffffffffffffffff SRR0 0000000000000000 SRR1 0000000000000000 PVR 0000000000800200 VRSAVE 0000000000000000 SPRG0 0000000000000000 SPRG1 0000000000000000 SPRG2 0000000000000000 SPRG3 0000000000000000 SPRG4 0000000000000000 SPRG5 0000000000000000 SPRG6 0000000000000000 SPRG7 0000000000000000 HSRR0 0000000000000000 HSRR1 0000000000000000 CFAR 0000000000000000 LPCR 0000000000020400 PTCR 0000000000000000 DAR 0000000000000000 DSISR 0000000000000000 kernel:trap=0xffffffea | pc=0x100 | msr=0x1000 This patch updates kvmppc_set_arch_compat() to use the host PVR value if 'compat_pvr' == 0 indicating that qemu doesn't want to enforce any specific PVR compat mode. The relevant part of the code might need a rework if PowerVM implements a support for `arch_compat == 0` in nestedv2 API. Fixes: 19d31c5f1157 ("KVM: PPC: Add support for nestedv2 guests") Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org> Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com> Signed-off-by: Amit Machhiwal <amachhiw@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240207054526.3720087-1-amachhiw@linux.ibm.com
2024-02-19KVM/VMX: Move VERW closer to VMentry for MDS mitigationPawan Gupta
During VMentry VERW is executed to mitigate MDS. After VERW, any memory access like register push onto stack may put host data in MDS affected CPU buffers. A guest can then use MDS to sample host data. Although likelihood of secrets surviving in registers at current VERW callsite is less, but it can't be ruled out. Harden the MDS mitigation by moving the VERW mitigation late in VMentry path. Note that VERW for MMIO Stale Data mitigation is unchanged because of the complexity of per-guest conditional VERW which is not easy to handle that late in asm with no GPRs available. If the CPU is also affected by MDS, VERW is unconditionally executed late in asm regardless of guest having MMIO access. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-6-a6216d83edb7%40linux.intel.com
2024-02-19KVM/VMX: Use BT+JNC, i.e. EFLAGS.CF to select VMRESUME vs. VMLAUNCHSean Christopherson
Use EFLAGS.CF instead of EFLAGS.ZF to track whether to use VMRESUME versus VMLAUNCH. Freeing up EFLAGS.ZF will allow doing VERW, which clobbers ZF, for MDS mitigations as late as possible without needing to duplicate VERW for both paths. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-5-a6216d83edb7%40linux.intel.com
2024-02-19x86/bugs: Use ALTERNATIVE() instead of mds_user_clear static keyPawan Gupta
The VERW mitigation at exit-to-user is enabled via a static branch mds_user_clear. This static branch is never toggled after boot, and can be safely replaced with an ALTERNATIVE() which is convenient to use in asm. Switch to ALTERNATIVE() to use the VERW mitigation late in exit-to-user path. Also remove the now redundant VERW in exc_nmi() and arch_exit_to_user_mode(). Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-4-a6216d83edb7%40linux.intel.com
2024-02-19x86/entry_32: Add VERW just before userspace transitionPawan Gupta
As done for entry_64, add support for executing VERW late in exit to user path for 32-bit mode. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-3-a6216d83edb7%40linux.intel.com
2024-02-19x86/entry_64: Add VERW just before userspace transitionPawan Gupta
Mitigation for MDS is to use VERW instruction to clear any secrets in CPU Buffers. Any memory accesses after VERW execution can still remain in CPU buffers. It is safer to execute VERW late in return to user path to minimize the window in which kernel data can end up in CPU buffers. There are not many kernel secrets to be had after SWITCH_TO_USER_CR3. Add support for deploying VERW mitigation after user register state is restored. This helps minimize the chances of kernel data ending up into CPU buffers after executing VERW. Note that the mitigation at the new location is not yet enabled. Corner case not handled ======================= Interrupts returning to kernel don't clear CPUs buffers since the exit-to-user path is expected to do that anyways. But, there could be a case when an NMI is generated in kernel after the exit-to-user path has cleared the buffers. This case is not handled and NMI returning to kernel don't clear CPU buffers because: 1. It is rare to get an NMI after VERW, but before returning to userspace. 2. For an unprivileged user, there is no known way to make that NMI less rare or target it. 3. It would take a large number of these precisely-timed NMIs to mount an actual attack. There's presumably not enough bandwidth. 4. The NMI in question occurs after a VERW, i.e. when user state is restored and most interesting data is already scrubbed. Whats left is only the data that NMI touches, and that may or may not be of any interest. Suggested-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-2-a6216d83edb7%40linux.intel.com
2024-02-19x86/bugs: Add asm helpers for executing VERWPawan Gupta
MDS mitigation requires clearing the CPU buffers before returning to user. This needs to be done late in the exit-to-user path. Current location of VERW leaves a possibility of kernel data ending up in CPU buffers for memory accesses done after VERW such as: 1. Kernel data accessed by an NMI between VERW and return-to-user can remain in CPU buffers since NMI returning to kernel does not execute VERW to clear CPU buffers. 2. Alyssa reported that after VERW is executed, CONFIG_GCC_PLUGIN_STACKLEAK=y scrubs the stack used by a system call. Memory accesses during stack scrubbing can move kernel stack contents into CPU buffers. 3. When caller saved registers are restored after a return from function executing VERW, the kernel stack accesses can remain in CPU buffers(since they occur after VERW). To fix this VERW needs to be moved very late in exit-to-user path. In preparation for moving VERW to entry/exit asm code, create macros that can be used in asm. Also make VERW patching depend on a new feature flag X86_FEATURE_CLEAR_CPU_BUF. Reported-by: Alyssa Milburn <alyssa.milburn@intel.com> Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-1-a6216d83edb7%40linux.intel.com
2024-02-19ubd: pass queue_limits to blk_mq_alloc_diskChristoph Hellwig
Pass the few limits ubd imposes directly to blk_mq_alloc_disk instead of setting them one at a time. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240215070300.2200308-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19nfblock: pass queue_limits to blk_mq_alloc_diskChristoph Hellwig
Pass the queue limits directly to blk_alloc_disk instead of setting them one at a time. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Link: https://lore.kernel.org/r/20240215071055.2201424-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19block: pass a queue_limits argument to blk_alloc_diskChristoph Hellwig
Pass a queue_limits to blk_alloc_disk and apply it if non-NULL. This will allow allocating queues with valid queue limits instead of setting the values one at a time later. Also change blk_alloc_disk to return an ERR_PTR instead of just NULL which can't distinguish errors. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Link: https://lore.kernel.org/r/20240215071055.2201424-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19parisc: Fix stack unwinderGuenter Roeck
Debugging shows a large number of unaligned access traps in the unwinder code. Code analysis reveals a number of issues with this code: - handle_interruption is passed twice through dereference_kernel_function_descriptor() - ret_from_kernel_thread, syscall_exit, intr_return, _switch_to_ret, and _call_on_stack are passed through dereference_kernel_function_descriptor() even though they are not declared as function pointers. To fix the problems, drop one of the calls to dereference_kernel_function_descriptor() for handle_interruption, and compare the other pointers directly. Fixes: 6414b30b39f9 ("parisc: unwind: Avoid missing prototype warning for handle_interruption()") Fixes: 8e0ba125c2bf ("parisc/unwind: fix unwinder when CONFIG_64BIT is enabled") Cc: Helge Deller <deller@gmx.de> Cc: Sven Schnelle <svens@stackframe.org> Cc: John David Anglin <dave.anglin@bell.net> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: David Laight <David.Laight@ACULAB.COM> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Helge Deller <deller@gmx.de>
2024-02-19x86/resctrl: Separate arch and fs resctrl locksJames Morse
resctrl has one mutex that is taken by the architecture-specific code, and the filesystem parts. The two interact via cpuhp, where the architecture code updates the domain list. Filesystem handlers that walk the domains list should not run concurrently with the cpuhp callback modifying the list. Exposing a lock from the filesystem code means the interface is not cleanly defined, and creates the possibility of cross-architecture lock ordering headaches. The interaction only exists so that certain filesystem paths are serialised against CPU hotplug. The CPU hotplug code already has a mechanism to do this using cpus_read_lock(). MPAM's monitors have an overflow interrupt, so it needs to be possible to walk the domains list in irq context. RCU is ideal for this, but some paths need to be able to sleep to allocate memory. Because resctrl_{on,off}line_cpu() take the rdtgroup_mutex as part of a cpuhp callback, cpus_read_lock() must always be taken first. rdtgroup_schemata_write() already does this. Most of the filesystem code's domain list walkers are currently protected by the rdtgroup_mutex taken in rdtgroup_kn_lock_live(). The exceptions are rdt_bit_usage_show() and the mon_config helpers which take the lock directly. Make the domain list protected by RCU. An architecture-specific lock prevents concurrent writers. rdt_bit_usage_show() could walk the domain list using RCU, but to keep all the filesystem operations the same, this is changed to call cpus_read_lock(). The mon_config helpers send multiple IPIs, take the cpus_read_lock() in these cases. The other filesystem list walkers need to be able to sleep. Add cpus_read_lock() to rdtgroup_kn_lock_live() so that the cpuhp callbacks can't be invoked when file system operations are occurring. Add lockdep_assert_cpus_held() in the cases where the rdtgroup_kn_lock_live() call isn't obvious. Resctrl's domain online/offline calls now need to take the rdtgroup_mutex themselves. [ bp: Fold in a build fix: https://lore.kernel.org/r/87zfvwieli.ffs@tglx ] Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-25-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-19KVM: arm64: Add debugfs file for guest's ID registersMarc Zyngier
Debugging ID register setup can be a complicated affair. Give the kernel hacker a way to dump that state in an easy to parse way. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-27-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Snapshot all non-zero RES0/RES1 sysreg fields for later checkingMarc Zyngier
As KVM now strongly relies on accurately handling the RES0/RES1 bits on a number of paths, add a compile-time checker that will blow in the face of the innocent bystander, should they try to sneak in an update that changes any of these RES0/RES1 fields. It is expected that such an update will come with the relevant KVM update if needed. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-26-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Make FEAT_MOPS UNDEF if not advertised to the guestMarc Zyngier
We unconditionally enable FEAT_MOPS, which is obviously wrong. So let's only do that when it is advertised to the guest. Which means we need to rely on a per-vcpu HCRX_EL2 shadow register. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20240214131827.2856277-25-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Make AMU sysreg UNDEF if FEAT_AMU is not advertised to the guestMarc Zyngier
No AMU? No AMU! IF we see an AMU-related trap, let's turn it into an UNDEF! Reviewed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-24-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Make PIR{,E0}_EL1 UNDEF if S1PIE is not advertised to the guestMarc Zyngier
As part of the ongoing effort to honor the guest configuration, add the necessary checks to make PIR_EL1 and co UNDEF if not advertised to the guest, and avoid context switching them. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20240214131827.2856277-23-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Make TLBI OS/Range UNDEF if not advertised to the guestMarc Zyngier
Outer Shareable and Range TLBI instructions shouldn't be made available to the guest if they are not advertised. Use FGU to disable those, and set HCR_EL2.TLBIOS in the case the host doesn't have FGT. Note that in that later case, we cannot efficiently disable TLBI Range instructions, as this would require to trap all TLBIs. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20240214131827.2856277-22-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Streamline save/restore of HFG[RW]TR_EL2Marc Zyngier
The way we save/restore HFG[RW]TR_EL2 can now be simplified, and the Ampere erratum hack is the only thing that still stands out. Reviewed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-21-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Move existing feature disabling over to FGU infrastructureMarc Zyngier
We already trap a bunch of existing features for the purpose of disabling them (MAIR2, POR, ACCDATA, SME...). Let's move them over to our brand new FGU infrastructure. Reviewed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-20-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Propagate and handle Fine-Grained UNDEF bitsMarc Zyngier
In order to correctly honor our FGU bits, they must be converted into a set of FGT bits. They get merged as part of the existing FGT setting. Similarly, the UNDEF injection phase takes place when handling the trap. This results in a bit of rework in the FGT macros in order to help with the code generation, as burying per-CPU accesses in macros results in a lot of expansion, not to mention the vcpu->kvm access on nvhe (kern_hyp_va() is not optimisation-friendly). Reviewed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-19-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-19KVM: arm64: Add Fine-Grained UNDEF tracking informationMarc Zyngier
In order to efficiently handle system register access being disabled, and this resulting in an UNDEF exception being injected, we introduce the (slightly dubious) concept of Fine-Grained UNDEF, modeled after the architectural Fine-Grained Traps. For each FGT group, we keep a 64 bit word that has the exact same bit assignment as the corresponding FGT register, where a 1 indicates that trapping this register should result in an UNDEF exception being reinjected. So far, nothing populates this information, nor sets the corresponding trap bits. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-18-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>