1220 Commits
Author | SHA1 | Message | Date | |
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Pawan Gupta
|
7390db8aea |
x86/bhi: Add support for clearing branch history at syscall entry
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> |
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Linus Torvalds
|
1e3ad78334 |
x86/syscall: Don't force use of indirect calls for system calls
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> |
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Borislav Petkov (AMD)
|
4969d75dd9 |
x86/vdso: Fix rethunk patching for vdso-image-x32.o too
In a similar fashion to b388e57d4628 ("x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o") annotate vdso-image-x32.o too for objtool so that it gets annotated properly and the unused return thunk warning doesn't fire. Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202403251454.23df6278-lkp@intel.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/202403251454.23df6278-lkp@intel.com |
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Linus Torvalds
|
1d35aae78f |
Kbuild updates for v6.9
- Generate a list of built DTB files (arch/*/boot/dts/dtbs-list) - Use more threads when building Debian packages in parallel - Fix warnings shown during the RPM kernel package uninstallation - Change OBJECT_FILES_NON_STANDARD_*.o etc. to take a relative path to Makefile - Support GCC's -fmin-function-alignment flag - Fix a null pointer dereference bug in modpost - Add the DTB support to the RPM package - Various fixes and cleanups in Kconfig -----BEGIN PGP SIGNATURE----- iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAmX8HGIVHG1hc2FoaXJv eUBrZXJuZWwub3JnAAoJED2LAQed4NsGYfIQAIl/zEFoNVSHGR4TIvO7SIwkT4MM VAm0W6XRFaXfIGw8HL/MXe+U9jAyeQ9yL9uUVv8PqFTO+LzBbW1X1X97tlmrlQsC 7mdxbA1KJXwkwt4wH/8/EZQMwHr327vtVH4AilSm+gAaWMXaSKAye3ulKQQ2gevz vP6aOcfbHIWOPdxA53cLdSl9LOGrYNczKySHXKV9O39T81F+ko7wPpdkiMWw5LWG ISRCV8bdXli8j10Pmg8jlbevSKl4Z5FG2BVw/Cl8rQ5tBBoCzFsUPnnp9A29G8QP OqRhbwxtkSm67BMJAYdHnhjp/l0AOEbmetTGpna+R06hirOuXhR3vc6YXZxhQjff LmKaqfG5YchRALS1fNDsRUNIkQxVJade+tOUG+V4WbxHQKWX7Ghu5EDlt2/x7P0p +XLPE48HoNQLQOJ+pgIOkaEDl7WLfGhoEtEgprZBuEP2h39xcdbYJyF10ZAAR4UZ FF6J9lDHbf7v1uqD2YnAQJQ6jJ06CvN6/s6SdiJnCWSs5cYRW0fnYigSIuwAgGHZ c/QFECoGEflXGGuqZDl5iXiIjhWKzH2nADSVEs7maP47vapcMWb9gA7VBNoOr5M0 IXuFo1khChF4V2pxqlDj3H5TkDlFENYT/Wjh+vvjx8XplKCRKaSh+LaZ39hja61V dWH7BPecS44h4KXx =tFdl -----END PGP SIGNATURE----- Merge tag 'kbuild-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Generate a list of built DTB files (arch/*/boot/dts/dtbs-list) - Use more threads when building Debian packages in parallel - Fix warnings shown during the RPM kernel package uninstallation - Change OBJECT_FILES_NON_STANDARD_*.o etc. to take a relative path to Makefile - Support GCC's -fmin-function-alignment flag - Fix a null pointer dereference bug in modpost - Add the DTB support to the RPM package - Various fixes and cleanups in Kconfig * tag 'kbuild-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (67 commits) kconfig: tests: test dependency after shuffling choices kconfig: tests: add a test for randconfig with dependent choices kconfig: tests: support KCONFIG_SEED for the randconfig runner kbuild: rpm-pkg: add dtb files in kernel rpm kconfig: remove unneeded menu_is_visible() call in conf_write_defconfig() kconfig: check prompt for choice while parsing kconfig: lxdialog: remove unused dialog colors kconfig: lxdialog: fix button color for blackbg theme modpost: fix null pointer dereference kbuild: remove GCC's default -Wpacked-bitfield-compat flag kbuild: unexport abs_srctree and abs_objtree kbuild: Move -Wenum-{compare-conditional,enum-conversion} into W=1 kconfig: remove named choice support kconfig: use linked list in get_symbol_str() to iterate over menus kconfig: link menus to a symbol kbuild: fix inconsistent indentation in top Makefile kbuild: Use -fmin-function-alignment when available alpha: merge two entries for CONFIG_ALPHA_GAMMA alpha: merge two entries for CONFIG_ALPHA_EV4 kbuild: change DTC_FLAGS_<basetarget>.o to take the path relative to $(obj) ... |
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Linus Torvalds
|
685d982112 |
Core x86 changes for v6.9:
- The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code. - Propagate more RIP-relative addressing in assembly code, to generate slightly better code. - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options. - Rework the x86 idle code to cure RCU violations and to clean up the logic. - Clean up the vDSO Makefile logic. - Misc cleanups and fixes. [ Please note that there's a higher number of merge commits in this branch (three) than is usual in x86 topic trees. This happened due to the long testing lifecycle of the percpu changes that involved 3 merge windows, which generated a longer history and various interactions with other core x86 changes that we felt better about to carry in a single branch. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmXvB0gRHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1jUqRAAqnEQPiabF5acQlHrwviX+cjSobDlqtH5 9q2AQy9qaEHapzD0XMOxvFye6XIvehGOGxSPvk6CoviSxBND8rb56lvnsEZuLeBV Bo5QSIL2x42Zrvo11iPHwgXZfTIusU90sBuKDRFkYBAxY3HK2naMDZe8MAsYCUE9 nwgHF8DDc/NYiSOXV8kosWoWpNIkoK/STyH5bvTQZMqZcwyZ49AIeP1jGZb/prbC e/rbnlrq5Eu6brpM7xo9kELO0Vhd34urV14KrrIpdkmUKytW2KIsyvW8D6fqgDBj NSaQLLcz0pCXbhF+8Nqvdh/1coR4L7Ymt08P1rfEjCsQgb/2WnSAGUQuC5JoGzaj ngkbFcZllIbD9gNzMQ1n4Aw5TiO+l9zxCqPC/r58Uuvstr+K9QKlwnp2+B3Q73Ft rojIJ04NJL6lCHdDgwAjTTks+TD2PT/eBWsDfJ/1pnUWttmv9IjMpnXD5sbHxoiU 2RGGKnYbxXczYdq/ALYDWM6JXpfnJZcXL3jJi0IDcCSsb92xRvTANYFHnTfyzGfw EHkhbF4e4Vy9f6QOkSP3CvW5H26BmZS9DKG0J9Il5R3u2lKdfbb5vmtUmVTqHmAD Ulo5cWZjEznlWCAYSI/aIidmBsp9OAEvYd+X7Z5SBIgTfSqV7VWHGt0BfA1heiVv F/mednG0gGc= =3v4F -----END PGP SIGNATURE----- Merge tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: - The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code - Propagate more RIP-relative addressing in assembly code, to generate slightly better code - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options - Rework the x86 idle code to cure RCU violations and to clean up the logic - Clean up the vDSO Makefile logic - Misc cleanups and fixes * tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) x86/idle: Select idle routine only once x86/idle: Let prefer_mwait_c1_over_halt() return bool x86/idle: Cleanup idle_setup() x86/idle: Clean up idle selection x86/idle: Sanitize X86_BUG_AMD_E400 handling sched/idle: Conditionally handle tick broadcast in default_idle_call() x86: Increase brk randomness entropy for 64-bit systems x86/vdso: Move vDSO to mmap region x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o x86/retpoline: Ensure default return thunk isn't used at runtime x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32 x86/vdso: Use $(addprefix ) instead of $(foreach ) x86/vdso: Simplify obj-y addition x86/vdso: Consolidate targets and clean-files x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS ... |
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Linus Torvalds
|
86833aec44 |
A single update for the x86 entry code:
The current CR3 handling for kernel page table isolation in the paranoid return paths which are relevant for #NMI, #MCE, #VC, #DB and #DF is unconditionally writing CR3 with the value retrieved on exception entry. In the vast majority of cases when returning to the kernel this is a pointless exercise because CR3 was not modified on exception entry. The only situation where this is necessary is when the exception interrupts a entry from user before switching to kernel CR3 or interrupts an exit to user after switching back to user CR3. As CR3 writes can be expensive on some systems this becomes measurable overhead with high frequency #NMIs such as perf. Avoid this overhead by checking the CR3 value, which was saved on entry, and write it back to CR3 only when it us a user CR3. -----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmXvTXYTHHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYoYMED/40YXFa0si5/9LRh/LSYglxVe/RaXCn 3oU19oWFRxdHCCLYHeQdlQGrpugM773X+4EC1dE92QpYjFnuLhl5H10h3t2e+3Uw Q2VoWEo95FuJ2v7nqex7p2pglOvNjT2VBBlcFFdhqxiC1FCupXvU17nCcLeBsPkj wbY2Sq4DxPDoWhWMNK2jhCQNVyYYluJERylS5+j0CK8vhQghq1N1WjcB6tQiAYsa 7nXz2ZJeGF0jnvLanyhAVSHDKU7QOMO3zkQpaaMlGQ9izawupe5/Gbi8ouFieCh+ xoLnGo1sgtMOXInnYaJnCiwuc+WiVN3d83aO/s7NZi8ZF60ib72xhzsRip2Cu4aV kBtJaCVLFItQZ81HRSBABj6s9MLphHVm4AaOCvCIxK0ib5KDFaWy3tZpwTU4dvwX rcwKsQrSLlOOD5zqO5dZn+HX6hK2lsNeTPLfcKVqARGn5S9fITzYbUMlkhO/FGaj ZhIgadH8+rXwFDbgS6CGbVYKtM6Ncf/VBGFfE7tEOUQVUmLws3pdLiWo6I2QTGtw fCAeF9uYmvhtiKk0e2jotZdbAg6HP2XTQSZfBxQpRgY6AnYW+XyDezcN0X1eNMJC lmNC72WYxURHZUoOIxiiVzDS9kz7YTUo3pBHFrpQlNqGTqP8r+tAhUyou16yDK/0 2G9Mms/85u89MQ== =UcMe -----END PGP SIGNATURE----- Merge tag 'x86-entry-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 entry update from Thomas Gleixner: "A single update for the x86 entry code: The current CR3 handling for kernel page table isolation in the paranoid return paths which are relevant for #NMI, #MCE, #VC, #DB and #DF is unconditionally writing CR3 with the value retrieved on exception entry. In the vast majority of cases when returning to the kernel this is a pointless exercise because CR3 was not modified on exception entry. The only situation where this is necessary is when the exception interrupts a entry from user before switching to kernel CR3 or interrupts an exit to user after switching back to user CR3. As CR3 writes can be expensive on some systems this becomes measurable overhead with high frequency #NMIs such as perf. Avoid this overhead by checking the CR3 value, which was saved on entry, and write it back to CR3 only when it is a user CR3" * tag 'x86-entry-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry: Avoid redundant CR3 write on paranoid returns |
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Linus Torvalds
|
720c857907 |
Support for x86 Fast Return and Event Delivery (FRED):
FRED is a replacement for IDT event delivery on x86 and addresses most of the technical nightmares which IDT exposes: 1) Exception cause registers like CR2 need to be manually preserved in nested exception scenarios. 2) Hardware interrupt stack switching is suboptimal for nested exceptions as the interrupt stack mechanism rewinds the stack on each entry which requires a massive effort in the low level entry of #NMI code to handle this. 3) No hardware distinction between entry from kernel or from user which makes establishing kernel context more complex than it needs to be especially for unconditionally nestable exceptions like NMI. 4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a problem when the perf NMI takes a fault when collecting a stack trace. 5) Partial restore of ESP when returning to a 16-bit segment 6) Limitation of the vector space which can cause vector exhaustion on large systems. 7) Inability to differentiate NMI sources FRED addresses these shortcomings by: 1) An extended exception stack frame which the CPU uses to save exception cause registers. This ensures that the meta information for each exception is preserved on stack and avoids the extra complexity of preserving it in software. 2) Hardware interrupt stack switching is non-rewinding if a nested exception uses the currently interrupt stack. 3) The entry points for kernel and user context are separate and GS BASE handling which is required to establish kernel context for per CPU variable access is done in hardware. 4) NMIs are now nesting protected. They are only reenabled on the return from NMI. 5) FRED guarantees full restore of ESP 6) FRED does not put a limitation on the vector space by design because it uses a central entry points for kernel and user space and the CPUstores the entry type (exception, trap, interrupt, syscall) on the entry stack along with the vector number. The entry code has to demultiplex this information, but this removes the vector space restriction. The first hardware implementations will still have the current restricted vector space because lifting this limitation requires further changes to the local APIC. 7) FRED stores the vector number and meta information on stack which allows having more than one NMI vector in future hardware when the required local APIC changes are in place. The series implements the initial FRED support by: - Reworking the existing entry and IDT handling infrastructure to accomodate for the alternative entry mechanism. - Expanding the stack frame to accomodate for the extra 16 bytes FRED requires to store context and meta information - Providing FRED specific C entry points for events which have information pushed to the extended stack frame, e.g. #PF and #DB. - Providing FRED specific C entry points for #NMI and #MCE - Implementing the FRED specific ASM entry points and the C code to demultiplex the events - Providing detection and initialization mechanisms and the necessary tweaks in context switching, GS BASE handling etc. The FRED integration aims for maximum code reuse vs. the existing IDT implementation to the extent possible and the deviation in hot paths like context switching are handled with alternatives to minimalize the impact. The low level entry and exit paths are seperate due to the extended stack frame and the hardware based GS BASE swichting and therefore have no impact on IDT based systems. It has been extensively tested on existing systems and on the FRED simulation and as of now there are know outstanding problems. -----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmXuKPgTHHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYoWyUEACevJMHU+Ot9zqBPizSWxByM1uunHbp bjQXhaFeskd3mt7k7HU6GsPRSmC3q4lliP1Y9ypfbU0DvYSI2h/PhMWizjhmot2y nIvFpl51r/NsI+JHx1oXcFetz0eGHEqBui/4YQ/swgOCMymYgfqgHhazXTdldV3g KpH9/8W3AeGvw79uzXFH9tjBzTkbvywpam3v0LYNDJWTCuDkilyo8PjhsgRZD4x3 V9f1nLD7nSHZW8XLoktdJJ38bKwI2Lhao91NQ0ErwopekA4/9WphZEKsDpidUSXJ sn1O148oQ8X92IO2OaQje8XC5pLGr5GqQBGPWzRH56P/Vd3+WOwBxaFoU6Drxc5s tIe23ZjkVcpA8EEG7BQBZV1Un/NX7XaCCnMniOt0RauXw+1NaslX7t/tnUAh5F1V TWCH4D0I0oJ0qJ7kNliGn2BP3agYXOVg81xVEUjT6KfHcYU4ImUrwi+BkeNXuXtL Ch5ADnbYAcUjWLFnAmEmaRtfmfNGY5T7PeGFHW2RRkaOJ88v5g14Voo6gPJaDUPn wMQ0nLq1xN4xZWF6ZgfRqAhArvh20k38ZujRku5vXEqnhOugQ76TF2UYiFEwOXbQ 8jcM+yEBLGgBz7tGMwmIAml6kfxaFF1KPpdrtcPxNkGlbE6KTSuIolLx2YGUvlSU 6/O8nwZy49ckmQ== =Ib7w -----END PGP SIGNATURE----- Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 FRED support from Thomas Gleixner: "Support for x86 Fast Return and Event Delivery (FRED). FRED is a replacement for IDT event delivery on x86 and addresses most of the technical nightmares which IDT exposes: 1) Exception cause registers like CR2 need to be manually preserved in nested exception scenarios. 2) Hardware interrupt stack switching is suboptimal for nested exceptions as the interrupt stack mechanism rewinds the stack on each entry which requires a massive effort in the low level entry of #NMI code to handle this. 3) No hardware distinction between entry from kernel or from user which makes establishing kernel context more complex than it needs to be especially for unconditionally nestable exceptions like NMI. 4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a problem when the perf NMI takes a fault when collecting a stack trace. 5) Partial restore of ESP when returning to a 16-bit segment 6) Limitation of the vector space which can cause vector exhaustion on large systems. 7) Inability to differentiate NMI sources FRED addresses these shortcomings by: 1) An extended exception stack frame which the CPU uses to save exception cause registers. This ensures that the meta information for each exception is preserved on stack and avoids the extra complexity of preserving it in software. 2) Hardware interrupt stack switching is non-rewinding if a nested exception uses the currently interrupt stack. 3) The entry points for kernel and user context are separate and GS BASE handling which is required to establish kernel context for per CPU variable access is done in hardware. 4) NMIs are now nesting protected. They are only reenabled on the return from NMI. 5) FRED guarantees full restore of ESP 6) FRED does not put a limitation on the vector space by design because it uses a central entry points for kernel and user space and the CPUstores the entry type (exception, trap, interrupt, syscall) on the entry stack along with the vector number. The entry code has to demultiplex this information, but this removes the vector space restriction. The first hardware implementations will still have the current restricted vector space because lifting this limitation requires further changes to the local APIC. 7) FRED stores the vector number and meta information on stack which allows having more than one NMI vector in future hardware when the required local APIC changes are in place. The series implements the initial FRED support by: - Reworking the existing entry and IDT handling infrastructure to accomodate for the alternative entry mechanism. - Expanding the stack frame to accomodate for the extra 16 bytes FRED requires to store context and meta information - Providing FRED specific C entry points for events which have information pushed to the extended stack frame, e.g. #PF and #DB. - Providing FRED specific C entry points for #NMI and #MCE - Implementing the FRED specific ASM entry points and the C code to demultiplex the events - Providing detection and initialization mechanisms and the necessary tweaks in context switching, GS BASE handling etc. The FRED integration aims for maximum code reuse vs the existing IDT implementation to the extent possible and the deviation in hot paths like context switching are handled with alternatives to minimalize the impact. The low level entry and exit paths are seperate due to the extended stack frame and the hardware based GS BASE swichting and therefore have no impact on IDT based systems. It has been extensively tested on existing systems and on the FRED simulation and as of now there are no outstanding problems" * tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) x86/fred: Fix init_task thread stack pointer initialization MAINTAINERS: Add a maintainer entry for FRED x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly x86/fred: Invoke FRED initialization code to enable FRED x86/fred: Add FRED initialization functions x86/syscall: Split IDT syscall setup code into idt_syscall_init() KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled x86/traps: Add sysvec_install() to install a system interrupt handler x86/fred: FRED entry/exit and dispatch code x86/fred: Add a machine check entry stub for FRED x86/fred: Add a NMI entry stub for FRED x86/fred: Add a debug fault entry stub for FRED x86/idtentry: Incorporate definitions/declarations of the FRED entries x86/fred: Make exc_page_fault() work for FRED x86/fred: Allow single-step trap and NMI when starting a new task x86/fred: No ESPFIX needed when FRED is enabled ... |
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Daniel Micay
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3c6539b4c1 |
x86/vdso: Move vDSO to mmap region
The vDSO (and its initial randomization) was introduced in commit 2aae950b21e4 ("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu"), but had very low entropy. The entropy was improved in commit 394f56fe4801 ("x86_64, vdso: Fix the vdso address randomization algorithm"), but there is still improvement to be made. In principle there should not be executable code at a low entropy offset from the stack, since the stack and executable code having separate randomization is part of what makes ASLR stronger. Remove the only executable code near the stack region and give the vDSO the same randomized base as other mmap mappings including the linker and other shared objects. This results in higher entropy being provided and there's little to no advantage in separating this from the existing executable code there. This is already how other architectures like arm64 handle the vDSO. As an side, while it's sensible for userspace to reserve the initial mmap base as a region for executable code with a random gap for other mmap allocations, along with providing randomization within that region, there isn't much the kernel can do to help due to how dynamic linkers load the shared objects. This was extracted from the PaX RANDMMAP feature. [kees: updated commit log with historical details and other tweaks] Signed-off-by: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Closes: https://github.com/KSPP/linux/issues/280 Link: https://lore.kernel.org/r/20240210091827.work.233-kees@kernel.org |
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Masahiro Yamada
|
bf48d9b756 |
kbuild: change tool coverage variables to take the path relative to $(obj)
Commit 54b8ae66ae1a ("kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)") changed the syntax of per-file compiler flags. The situation is the same for the following variables: OBJECT_FILES_NON_STANDARD_<basetarget>.o GCOV_PROFILE_<basetarget>.o KASAN_SANITIZE_<basetarget>.o KMSAN_SANITIZE_<basetarget>.o KMSAN_ENABLE_CHECKS_<basetarget>.o UBSAN_SANITIZE_<basetarget>.o KCOV_INSTRUMENT_<basetarget>.o KCSAN_SANITIZE_<basetarget>.o KCSAN_INSTRUMENT_BARRIERS_<basetarget>.o The <basetarget> is the filename of the target with its directory and suffix stripped. This syntax comes into a trouble when two files with the same basename appear in one Makefile, for example: obj-y += dir1/foo.o obj-y += dir2/foo.o OBJECT_FILES_NON_STANDARD_foo.o := y OBJECT_FILES_NON_STANDARD_foo.o is applied to both dir1/foo.o and dir2/foo.o. This syntax is not flexbile enough to handle cases where one of them is a standard object, but the other is not. It is more sensible to use the relative path to the Makefile, like this: obj-y += dir1/foo.o OBJECT_FILES_NON_STANDARD_dir1/foo.o := y obj-y += dir2/foo.o OBJECT_FILES_NON_STANDARD_dir2/foo.o := y To maintain the current behavior, I made adjustments to the following two Makefiles: - arch/x86/entry/vdso/Makefile, which compiles vclock_gettime.o, vgetcpu.o, and their vdso32 variants. - arch/x86/kvm/Makefile, which compiles vmx/vmenter.o and svm/vmenter.o Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> Acked-by: Sean Christopherson <seanjc@google.com> |
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Ingo Molnar
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b7bcffe752 |
x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together
The fresh changes to the vDSO Makefile in: 289d0a475c3e ("x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32") 329b77b59f83 ("x86/vdso: Simplify obj-y addition") Conflicted with a pending change in: b388e57d4628e ("x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o") Which was resolved in a simple fasion in this merge commit: f14df823a61e ("Merge branch 'x86/vdso' into x86/core, to resolve conflict and to prepare for dependent changes") ... but all these changes make me look and notice a bit of historic baggage left in the Makefile: - Disordered build rules where non-standard build attributes relating to were placed sometimes several lines after - and sometimes *before* the .o build rules of the object files... Functional but inconsistent. - Inconsistent vertical spacing, stray whitespaces, inconsistent spelling of 'vDSO' over the years, a few spelling mistakes and inconsistent capitalization of comment blocks. Tidy it all up. No functional changes intended. Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Ingo Molnar
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f14df823a6 |
Merge branch 'x86/vdso' into x86/core, to resolve conflict and to prepare for dependent changes
Conflicts: arch/x86/entry/vdso/Makefile We also want to change arch/x86/entry/vdso/Makefile in a followup commit, so merge the trees for this. Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Josh Poimboeuf
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b388e57d46 |
x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o
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 |
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Pawan Gupta
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a0e2dab44d |
x86/entry_32: Add VERW just before userspace transition
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 |
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Pawan Gupta
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3c7501722e |
x86/entry_64: Add VERW just before userspace transition
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 |
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Pawan Gupta
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baf8361e54 |
x86/bugs: Add asm helpers for executing VERW
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 |
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Ingo Molnar
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4589f199eb |
Merge branch 'x86/bugs' into x86/core, to pick up pending changes before dependent patches
Merge in pending alternatives patching infrastructure changes, before applying more patches. Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Ingo Molnar
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03c11eb3b1 |
Linux 6.8-rc4
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmXJK4UeHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGHsYH/jKmzKXDRsBCcw/Q HGUvFtpohWBOpN6efdf0nxilQisuyQrqKB9fnwvfcdE60VpqMJXFMdlFh/fonxPl JMbpk9y5uw48IJZA43NwTxUrjZ4wyWzv4ZF6YWa+5WdTAJpPLEPhhnLxcHOKklMr 5Cm/7B/M7eB2BXBfc45b1pkKN22q9OXvjaKxZ+5wYmiMxS+GC8l8jiJ/WlHX78PR eLgsa1v732f2D7YF75wVhaoYepR+QzA9wTKqhjMNCEaVc2PQhA2JRsBXEt84qEIa FZigmf7LLc4ed9YA2XjRBZhAehe3cZVJZ1lasW37IATS921La2WfKuiysICJOtyT bGjK8tk= =Pt7W -----END PGP SIGNATURE----- Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch Conflicts: arch/x86/include/asm/percpu.h arch/x86/include/asm/text-patching.h Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Josh Poimboeuf
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4461438a84 |
x86/retpoline: Ensure default return thunk isn't used at runtime
Make sure the default return thunk is not used after all return instructions have been patched by the alternatives because the default return thunk is insufficient when it comes to mitigating Retbleed or SRSO. Fix based on an earlier version by David Kaplan <david.kaplan@amd.com>. [ bp: Fix the compilation error of warn_thunk_thunk being an invisible symbol, hoist thunk macro into calling.h ] Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231010171020.462211-4-david.kaplan@amd.com Link: https://lore.kernel.org/r/20240104132446.GEZZaxnrIgIyat0pqf@fat_crate.local |
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Masahiro Yamada
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289d0a475c |
x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32
In arch/x86/Kconfig, COMPAT_32 is defined as (IA32_EMULATION || X86_32). Use it to eliminate redundancy in Makefile. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231121235701.239606-5-masahiroy@kernel.org |
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Masahiro Yamada
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ac9275b3b4 |
x86/vdso: Use $(addprefix ) instead of $(foreach )
$(addprefix ) is slightly shorter and more intuitive. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231121235701.239606-4-masahiroy@kernel.org |
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Masahiro Yamada
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329b77b59f |
x86/vdso: Simplify obj-y addition
Add objects to obj-y in a more straightforward way. CONFIG_X86_32 and CONFIG_IA32_EMULATION are not enabled simultaneously, but even if they are, Kbuild graciously deduplicates obj-y entries. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231121235701.239606-3-masahiroy@kernel.org |
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Masahiro Yamada
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31a4ebee0d |
x86/vdso: Consolidate targets and clean-files
'targets' and 'clean-files' do not need to list the same files because the files listed in 'targets' are cleaned up. Refactor the code. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231121235701.239606-2-masahiroy@kernel.org |
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H. Peter Anvin (Intel)
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cdd99dd873 |
x86/fred: Add FRED initialization functions
Add cpu_init_fred_exceptions() to: - Set FRED entrypoints for events happening in ring 0 and 3. - Specify the stack level for IRQs occurred ring 0. - Specify dedicated event stacks for #DB/NMI/#MCE/#DF. - Enable FRED and invalidtes IDT. - Force 32-bit system calls to use "int $0x80" only. Add fred_complete_exception_setup() to: - Initialize system_vectors as done for IDT systems. - Set unused sysvec_table entries to fred_handle_spurious_interrupt(). Co-developed-by: Xin Li <xin3.li@intel.com> Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-35-xin3.li@intel.com |
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Xin Li
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2e670358ec |
x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI
In IRQ/NMI induced VM exits, KVM VMX needs to execute the respective handlers, which requires the software to create a FRED stack frame, and use it to invoke the handlers. Add fred_irq_entry_from_kvm() for this job. Export fred_entry_from_kvm() because VMX can be compiled as a module. Suggested-by: Sean Christopherson <seanjc@google.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-32-xin3.li@intel.com |
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Peter Zijlstra (Intel)
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2333f3c473 |
x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code
PUSH_AND_CLEAR_REGS could be used besides actual entry code; in that case %rbp shouldn't be cleared (otherwise the frame pointer is destroyed) and UNWIND_HINT shouldn't be added. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-31-xin3.li@intel.com |
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Xin Li
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5105e7687a |
x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user
If the stack frame contains an invalid user context (e.g. due to invalid SS, a non-canonical RIP, etc.) the ERETU instruction will trap (#SS or #GP). From a Linux point of view, this really should be considered a user space failure, so use the standard fault fixup mechanism to intercept the fault, fix up the exception frame, and redirect execution to fred_entrypoint_user. The end result is that it appears just as if the hardware had taken the exception immediately after completing the transition to user space. Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-30-xin3.li@intel.com |
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H. Peter Anvin (Intel)
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51ef2a4da7 |
x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled
Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled, otherwise the existing IDT code is chosen. Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-29-xin3.li@intel.com |
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Xin Li
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8f4a29b0e8 |
x86/traps: Add sysvec_install() to install a system interrupt handler
Add sysvec_install() to install a system interrupt handler into the IDT or the FRED system interrupt handler table. Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-28-xin3.li@intel.com |
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H. Peter Anvin (Intel)
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14619d912b |
x86/fred: FRED entry/exit and dispatch code
The code to actually handle kernel and event entry/exit using FRED. It is split up into two files thus: - entry_64_fred.S contains the actual entrypoints and exit code, and saves and restores registers. - entry_fred.c contains the two-level event dispatch code for FRED. The first-level dispatch is on the event type, and the second-level is on the event vector. [ bp: Fold in an allmodconfig clang build fix: https://lore.kernel.org/r/20240129064521.5168-1-xin3.li@intel.com and a CONFIG_IA32_EMULATION=n build fix: https://lore.kernel.org/r/20240127093728.1323-3-xin3.li@intel.com] Suggested-by: Thomas Gleixner <tglx@linutronix.de> Originally-by: Megha Dey <megha.dey@intel.com> Co-developed-by: Xin Li <xin3.li@intel.com> Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231209214214.2932-1-xin3.li@intel.com |
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Xin Li
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ee63291aa8 |
x86/ptrace: Cleanup the definition of the pt_regs structure
struct pt_regs is hard to read because the member or section related comments are not aligned with the members. The 'cs' and 'ss' members of pt_regs are type of 'unsigned long' while in reality they are only 16-bit wide. This works so far as the remaining space is unused, but FRED will use the remaining bits for other purposes. To prepare for FRED: - Cleanup the formatting - Convert 'cs' and 'ss' to u16 and embed them into an union with a u64 - Fixup the related printk() format strings Suggested-by: Thomas Gleixner <tglx@linutronix.de> Originally-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-14-xin3.li@intel.com |
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Xin Li
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3167b37f82 |
x86/entry: Remove idtentry_sysvec from entry_{32,64}.S
idtentry_sysvec is really just DECLARE_IDTENTRY defined in <asm/idtentry.h>, no need to define it separately. Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-3-xin3.li@intel.com |
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Lai Jiangshan
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bb99836199 |
x86/entry: Avoid redundant CR3 write on paranoid returns
The CR3 restore happens in: 1. #NMI return. 2. paranoid_exit() (i.e. #MCE, #VC, #DB and #DF return) Contrary to the implication in commit 21e94459110252 ("x86/mm: Optimize RESTORE_CR3"), the kernel never modifies CR3 in any of these exceptions, except for switching from user to kernel pagetables under PTI. That means that most of the time when returning from an exception that interrupted the kernel no CR3 restore is necessary. Writing CR3 is expensive on some machines. Most of the time because the interrupt might have come during kernel entry before the user to kernel CR3 switch or the during exit after the kernel to user switch. In the former case skipping the restore would be correct, but definitely not for the latter. So check the saved CR3 value and restore it only, if it is a user CR3. Give the macro a new name to clarify its usage, and remove a comment that was describing the original behaviour along with the not longer needed jump label. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240108113950.360438-1-jackmanb@google.com [Rewrote commit message; responded to review comments] Change-Id: I6e56978c4753fb943a7897ff101f519514fa0827 |
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Linus Torvalds
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c299010061 |
asm-generic cleanups for 6.8
A series from Baoquan He cleans up the asm-generic/io.h to remove the ioremap_uc() definition from everything except x86, which still needs it for pre-PAT systems. This series notably contains a patch from Jiaxun Yang that converts MIPS to use asm-generic/io.h like every other architecture does, enabling future cleanups. Some of my own patches fix -Wmissing-prototype warnings in architecture specific code across several architectures. This is now needed as the warning is enabled by default. There are still some remaining warnings in minor platforms, but the series should catch most of the widely used ones make them more consistent with one another. David McKay fixes a bug in __generic_cmpxchg_local() when this is used on 64-bit architectures. This could currently only affect parisc64 and sparc64. Additional cleanups address from Linus Walleij, Uwe Kleine-König, Thomas Huth, and Kefeng Wang help reduce unnecessary inconsistencies between architectures. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEiK/NIGsWEZVxh/FrYKtH/8kJUicFAmWeak8ACgkQYKtH/8kJ UidSiQ/+LL1WTO9d3Zx5HI0GGGjaIYpYs6jUNSf9Y5GPQiOrvjfEWj7CU11/4vxl GlQRpRyncYm8Eiz0Qu+aNxZFiiMah8Uful75yfbX8P1L4EPTbAYNDjkyNJrTjIAK jPK4sl8awIrapOeFUz++PsEj22R/4Is4f0mo+CqoCkL5RKlHe5oFdXzcwjmds4yK CvU6Ldn+M7FZ3EItMdjXaB3D3HS9uictFiO5JByZY8p+IcqgNRI/iHNnZIMsltJ+ XjDi0DG+x4jCj6teElSchw7AofE4OcNSP3xbR1PLKv6+xBLGYaAGZhNuPTz88eV/ Gj0loDQrrR5McGUfDBRHK9zN2Jd0O/FKnfh9kLOt1FLFyGPvC78Q/2HkpVCjbBr2 Pr1aqhLDHA+tGNSsThsV8RUa8/tiEnxAki43tfBFS3SEKhtQsTm2g1z4miwbE3p0 BJIrSgTqrP/SBq7a9z/thPrkzdZcNuA9FUETTbaMeUlJS51n1V9E5A1t7sOG7jaI vV/gbuR6FjvD49mTyQiOSCt3V4ygRqgN1Q+C4QM8WLqq2keUq0AhGodquv8F78in J3x2j2r27lHY7jKf8B0dua/JXAsF20u8qD6yDQ9ymkjt/MWhGXBgK0jpT7RTIuMS e2jmTywUVD4UohAcx3inkOojUhIJ5KDB0I4Pzv4zWcHNbyFNKcY= =4VQl -----END PGP SIGNATURE----- Merge tag 'asm-generic-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cleanups from Arnd Bergmann: "A series from Baoquan He cleans up the asm-generic/io.h to remove the ioremap_uc() definition from everything except x86, which still needs it for pre-PAT systems. This series notably contains a patch from Jiaxun Yang that converts MIPS to use asm-generic/io.h like every other architecture does, enabling future cleanups. Some of my own patches fix -Wmissing-prototype warnings in architecture specific code across several architectures. This is now needed as the warning is enabled by default. There are still some remaining warnings in minor platforms, but the series should catch most of the widely used ones make them more consistent with one another. David McKay fixes a bug in __generic_cmpxchg_local() when this is used on 64-bit architectures. This could currently only affect parisc64 and sparc64. Additional cleanups address from Linus Walleij, Uwe Kleine-König, Thomas Huth, and Kefeng Wang help reduce unnecessary inconsistencies between architectures" * tag 'asm-generic-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: Fix 32 bit __generic_cmpxchg_local Hexagon: Make pfn accessors statics inlines ARC: mm: Make virt_to_pfn() a static inline mips: remove extraneous asm-generic/iomap.h include sparc: Use $(kecho) to announce kernel images being ready arm64: vdso32: Define BUILD_VDSO32_64 to correct prototypes csky: fix arch_jump_label_transform_static override arch: add do_page_fault prototypes arch: add missing prepare_ftrace_return() prototypes arch: vdso: consolidate gettime prototypes arch: include linux/cpu.h for trap_init() prototype arch: fix asm-offsets.c building with -Wmissing-prototypes arch: consolidate arch_irq_work_raise prototypes hexagon: Remove CONFIG_HEXAGON_ARCH_VERSION from uapi header asm/io: remove unnecessary xlate_dev_mem_ptr() and unxlate_dev_mem_ptr() mips: io: remove duplicated codes arch/*/io.h: remove ioremap_uc in some architectures mips: add <asm-generic/io.h> including |
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Breno Leitao
|
1da8d2172c |
x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY
Step 8/10 of the namespace unification of CPU mitigations related Kconfig options. Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-9-leitao@debian.org |
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Breno Leitao
|
aefb2f2e61 |
x86/bugs: Rename CONFIG_RETPOLINE => CONFIG_MITIGATION_RETPOLINE
Step 5/10 of the namespace unification of CPU mitigations related Kconfig options. [ mingo: Converted a few more uses in comments/messages as well. ] Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ariel Miculas <amiculas@cisco.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-6-leitao@debian.org |
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Breno Leitao
|
ea4654e088 |
x86/bugs: Rename CONFIG_PAGE_TABLE_ISOLATION => CONFIG_MITIGATION_PAGE_TABLE_ISOLATION
Step 4/10 of the namespace unification of CPU mitigations related Kconfig options. [ mingo: Converted new uses that got added since the series was posted. ] Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-5-leitao@debian.org |
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Linus Torvalds
|
063a7ce32d |
lsm/stable-6.8 PR 20240105
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The first syscall simply lists the LSMs enabled, while the second and third get and set the current process' LSM attributes. Yes, these syscalls may provide similar functionality to what can be found under /proc or /sys, but they were designed to support multiple, simultaneaous (stacked) LSMs from the start as opposed to the current /proc based solutions which were created at a time when only one LSM was allowed to be active at a given time. We have spent considerable time discussing ways to extend the existing /proc interfaces to support multiple, simultaneaous LSMs and even our best ideas have been far too ugly to support as a kernel API; after +20 years in the kernel, I felt the LSM layer had established itself enough to justify a handful of syscalls. Support amongst the individual LSM developers has been nearly unanimous, with a single objection coming from Tetsuo (TOMOYO) as he is worried that the LSM_ID_XXX token concept will make it more difficult for out-of-tree LSMs to survive. Several members of the LSM community have demonstrated the ability for out-of-tree LSMs to continue to exist by picking high/unused LSM_ID values as well as pointing out that many kernel APIs rely on integer identifiers, e.g. syscalls (!), but unfortunately Tetsuo's objections remain. My personal opinion is that while I have no interest in penalizing out-of-tree LSMs, I'm not going to penalize in-tree development to support out-of-tree development, and I view this as a necessary step forward to support the push for expanded LSM stacking and reduce our reliance on /proc and /sys which has occassionally been problematic for some container users. Finally, we have included the linux-api folks on (all?) recent revisions of the patchset and addressed all of their concerns. - Add a new security_file_ioctl_compat() LSM hook to handle the 32-bit ioctls on 64-bit systems problem. This patch includes support for all of the existing LSMs which provide ioctl hooks, although it turns out only SELinux actually cares about the individual ioctls. It is worth noting that while Casey (Smack) and Tetsuo (TOMOYO) did not give explicit ACKs to this patch, they did both indicate they are okay with the changes. - Fix a potential memory leak in the CALIPSO code when IPv6 is disabled at boot. While it's good that we are fixing this, I doubt this is something users are seeing in the wild as you need to both disable IPv6 and then attempt to configure IPv6 labeled networking via NetLabel/CALIPSO; that just doesn't make much sense. Normally this would go through netdev, but Jakub asked me to take this patch and of all the trees I maintain, the LSM tree seemed like the best fit. - Update the LSM MAINTAINERS entry with additional information about our process docs, patchwork, bug reporting, etc. I also noticed that the Lockdown LSM is missing a dedicated MAINTAINERS entry so I've added that to the pull request. I've been working with one of the major Lockdown authors/contributors to see if they are willing to step up and assume a Lockdown maintainer role; hopefully that will happen soon, but in the meantime I'll continue to look after it. - Add a handful of mailmap entries for Serge Hallyn and myself. * tag 'lsm-pr-20240105' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (27 commits) lsm: new security_file_ioctl_compat() hook lsm: Add a __counted_by() annotation to lsm_ctx.ctx calipso: fix memory leak in netlbl_calipso_add_pass() selftests: remove the LSM_ID_IMA check in lsm/lsm_list_modules_test MAINTAINERS: add an entry for the lockdown LSM MAINTAINERS: update the LSM entry mailmap: add entries for Serge Hallyn's dead accounts mailmap: update/replace my old email addresses lsm: mark the lsm_id variables are marked as static lsm: convert security_setselfattr() to use memdup_user() lsm: align based on pointer length in lsm_fill_user_ctx() lsm: consolidate buffer size handling into lsm_fill_user_ctx() lsm: correct error codes in security_getselfattr() lsm: cleanup the size counters in security_getselfattr() lsm: don't yet account for IMA in LSM_CONFIG_COUNT calculation lsm: drop LSM_ID_IMA LSM: selftests for Linux Security Module syscalls SELinux: Add selfattr hooks AppArmor: Add selfattr hooks Smack: implement setselfattr and getselfattr hooks ... |
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Linus Torvalds
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2fdbcf715a |
x86/entry changes for v6.8:
- Optimize common_interrupt_return() - Harden the return-to-user code by making a CONFIG_DEBUG_ENTRY=y check unconditional & moving it closer to the IRET. Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmWb3EcRHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1jY7hAAwotnWLkLAuPGeEf9zVAb7SXYxyHQphia s1pdKbLPOZdhS066ek9WhChcMQMAs/IT1PFYjXCwZ83a/wP6oNZAEUzOOBsDU+83 ZDoIBcwh7kP0gGTAI8vQ4tRA8lszkwgT19uwF0+qiAnvmKB8Flvl+x4SEsSYI26m mly7xMwOWn+z4aJ/NuKQqJ0MM/GX1/lqxiRrPV5B95usY62vI6Bfc8qIAA1GkPDc TkZzB7SBLhsd8vnmdO9MzAY641efpp8fGYUNnk1ighbC9OPhvoI8nXnQ/lD1XauC /1pJC/Ikxz3HVLUNx+5DcjxnuB/b5CDIkgqsgbMTp40of0Z8g4CEna4QEcpugCDC vbdlOQfdGv6/3tQtDm29bPLBY3eOfx5b7JEr9BOyJXWCzaxOGlOozMv18dYQZkmM PYH8DHrIGHz3nudJ3lBh1ki27WfClRsrR0P9sv8K/Hkbnemg/FUZiz7ex/G3NIfe J3QcrJAjhdHNdSd81x+C33ANedJLYjEJyanejaCjSH3ZnZpXkwyHRgKrqvUizqND 4TRjQQcAy3ZScsrzHleN1KInzbIiNyA0ct6JD9igiQgUvw7pqO8Xhs7Xjm+jQBcD Up6bJ30dLglrK9UfIxpOLdjJH1eTiUtTcg2jIfynQlee+JgfUVoniUwViUdSKMyp Ji5+UM6HaTM= =C5sU -----END PGP SIGNATURE----- Merge tag 'x86-entry-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 entry updates from Ingo Molnar: - Optimize common_interrupt_return() - Harden the return-to-user code by making a CONFIG_DEBUG_ENTRY=y check unconditional & moving it closer to the IRET. * tag 'x86-entry-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry: Harden return-to-user x86/entry: Optimize common_interrupt_return() |
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Linus Torvalds
|
8c9440fea7 |
vfs-6.8.mount
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZZU0CgAKCRCRxhvAZXjc osncAQDSJK0frJL+72NqXxa4YNzivrnuw6fhp5iaDAEqxdm8ygEAoJWyh7Rmkt8G drAXWGyGnCYqv7UgC6axLyciid7TxQg= =vJuv -----END PGP SIGNATURE----- Merge tag 'vfs-6.8.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs mount updates from Christian Brauner: "This contains the work to retrieve detailed information about mounts via two new system calls. This is hopefully the beginning of the end of the saga that started with fsinfo() years ago. The LWN articles in [1] and [2] can serve as a summary so we can avoid rehashing everything here. At LSFMM in May 2022 we got into a room and agreed on what we want to do about fsinfo(). Basically, split it into pieces. This is the first part of that agreement. Specifically, it is concerned with retrieving information about mounts. So this only concerns the mount information retrieval, not the mount table change notification, or the extended filesystem specific mount option work. That is separate work. Currently mounts have a 32bit id. Mount ids are already in heavy use by libmount and other low-level userspace but they can't be relied upon because they're recycled very quickly. We agreed that mounts should carry a unique 64bit id by which they can be referenced directly. This is now implemented as part of this work. The new 64bit mount id is exposed in statx() through the new STATX_MNT_ID_UNIQUE flag. If the flag isn't raised the old mount id is returned. If it is raised and the kernel supports the new 64bit mount id the flag is raised in the result mask and the new 64bit mount id is returned. New and old mount ids do not overlap so they cannot be conflated. Two new system calls are introduced that operate on the 64bit mount id: statmount() and listmount(). A summary of the api and usage can be found on LWN as well (cf. [3]) but of course, I'll provide a summary here as well. Both system calls rely on struct mnt_id_req. Which is the request struct used to pass the 64bit mount id identifying the mount to operate on. It is extensible to allow for the addition of new parameters and for future use in other apis that make use of mount ids. statmount() mimicks the semantics of statx() and exposes a set flags that userspace may raise in mnt_id_req to request specific information to be retrieved. A statmount() call returns a struct statmount filled in with information about the requested mount. Supported requests are indicated by raising the request flag passed in struct mnt_id_req in the @mask argument in struct statmount. Currently we do support: - STATMOUNT_SB_BASIC: Basic filesystem info - STATMOUNT_MNT_BASIC Mount information (mount id, parent mount id, mount attributes etc) - STATMOUNT_PROPAGATE_FROM Propagation from what mount in current namespace - STATMOUNT_MNT_ROOT Path of the root of the mount (e.g., mount --bind /bla /mnt returns /bla) - STATMOUNT_MNT_POINT Path of the mount point (e.g., mount --bind /bla /mnt returns /mnt) - STATMOUNT_FS_TYPE Name of the filesystem type as the magic number isn't enough due to submounts The string options STATMOUNT_MNT_{ROOT,POINT} and STATMOUNT_FS_TYPE are appended to the end of the struct. Userspace can use the offsets in @fs_type, @mnt_root, and @mnt_point to reference those strings easily. The struct statmount reserves quite a bit of space currently for future extensibility. This isn't really a problem and if this bothers us we can just send a follow-up pull request during this cycle. listmount() is given a 64bit mount id via mnt_id_req just as statmount(). It takes a buffer and a size to return an array of the 64bit ids of the child mounts of the requested mount. Userspace can thus choose to either retrieve child mounts for a mount in batches or iterate through the child mounts. For most use-cases it will be sufficient to just leave space for a few child mounts. But for big mount tables having an iterator is really helpful. Iterating through a mount table works by setting @param in mnt_id_req to the mount id of the last child mount retrieved in the previous listmount() call" Link: https://lwn.net/Articles/934469 [1] Link: https://lwn.net/Articles/829212 [2] Link: https://lwn.net/Articles/950569 [3] * tag 'vfs-6.8.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: add selftest for statmount/listmount fs: keep struct mnt_id_req extensible wire up syscalls for statmount/listmount add listmount(2) syscall statmount: simplify string option retrieval statmount: simplify numeric option retrieval add statmount(2) syscall namespace: extract show_path() helper mounts: keep list of mounts in an rbtree add unique mount ID |
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Miklos Szeredi
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d8b0f54650
|
wire up syscalls for statmount/listmount
Wire up all archs. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Link: https://lore.kernel.org/r/20231025140205.3586473-7-mszeredi@redhat.com Reviewed-by: Ian Kent <raven@themaw.net> Signed-off-by: Christian Brauner <brauner@kernel.org> |
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Thomas Gleixner
|
55617fb991 |
x86/entry: Do not allow external 0x80 interrupts
The INT 0x80 instruction is used for 32-bit x86 Linux syscalls. The kernel expects to receive a software interrupt as a result of the INT 0x80 instruction. However, an external interrupt on the same vector also triggers the same codepath. An external interrupt on vector 0x80 will currently be interpreted as a 32-bit system call, and assuming that it was a user context. Panic on external interrupts on the vector. To distinguish software interrupts from external ones, the kernel checks the APIC ISR bit relevant to the 0x80 vector. For software interrupts, this bit will be 0. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@vger.kernel.org> # v6.0+ |
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Thomas Gleixner
|
be5341eb0d |
x86/entry: Convert INT 0x80 emulation to IDTENTRY
There is no real reason to have a separate ASM entry point implementation for the legacy INT 0x80 syscall emulation on 64-bit. IDTENTRY provides all the functionality needed with the only difference that it does not: - save the syscall number (AX) into pt_regs::orig_ax - set pt_regs::ax to -ENOSYS Both can be done safely in the C code of an IDTENTRY before invoking any of the syscall related functions which depend on this convention. Aside of ASM code reduction this prepares for detecting and handling a local APIC injected vector 0x80. [ kirill.shutemov: More verbose comments ] Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@vger.kernel.org> # v6.0+ |
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Arnd Bergmann
|
42874e4eb3 |
arch: vdso: consolidate gettime prototypes
The VDSO functions are defined as globals in the kernel sources but intended to be called from userspace, so there is no need to declare them in a kernel side header. Without a prototype, this now causes warnings such as arch/mips/vdso/vgettimeofday.c:14:5: error: no previous prototype for '__vdso_clock_gettime' [-Werror=missing-prototypes] arch/mips/vdso/vgettimeofday.c:28:5: error: no previous prototype for '__vdso_gettimeofday' [-Werror=missing-prototypes] arch/mips/vdso/vgettimeofday.c:36:5: error: no previous prototype for '__vdso_clock_getres' [-Werror=missing-prototypes] arch/mips/vdso/vgettimeofday.c:42:5: error: no previous prototype for '__vdso_clock_gettime64' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:254:1: error: no previous prototype for '__vdso_clock_gettime' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:282:1: error: no previous prototype for '__vdso_clock_gettime_stick' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:307:1: error: no previous prototype for '__vdso_gettimeofday' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:343:1: error: no previous prototype for '__vdso_gettimeofday_stick' [-Werror=missing-prototypes] Most architectures have already added workarounds for these by adding declarations somewhere, but since these are all compatible, we should really just have one copy, with an #ifdef check for the 32-bit vs 64-bit variant and use that everywhere. Unfortunately, the sparc an um versions are currently incompatible since they never added support for __vdso_clock_gettime64() in 32-bit userland. For the moment, I'm leaving this one out, as I can't easily test it and it requires a larger rework. Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> |
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Peter Zijlstra
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1e4d3001f5 |
x86/entry: Harden return-to-user
Make the CONFIG_DEBUG_ENTRY=y check that validates CS is a user segment unconditional and move it nearer to IRET. PRE: 140,026,608 cycles:k ( +- 0.01% ) 236,696,176 instructions:k # 1.69 insn per cycle ( +- 0.00% ) POST: 139,957,681 cycles:k ( +- 0.01% ) 236,681,819 instructions:k # 1.69 insn per cycle ( +- 0.00% ) (this is with --repeat 100 and the run-to-run variance is bigger than the difference shown) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231120143626.753200755@infradead.org |
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Peter Zijlstra
|
c516213726 |
x86/entry: Optimize common_interrupt_return()
The code in common_interrupt_return() does a bunch of unconditional work that is really only needed on PTI kernels. Specifically it unconditionally copies the IRET frame back onto the entry stack, swizzles onto the entry stack and does IRET from there. However, without PTI we can simply IRET from whatever stack we're on. ivb-ep, mitigations=off, gettid-1m: PRE: 140,118,538 cycles:k ( +- 0.01% ) 236,692,878 instructions:k # 1.69 insn per cycle ( +- 0.00% ) POST: 140,026,608 cycles:k ( +- 0.01% ) 236,696,176 instructions:k # 1.69 insn per cycle ( +- 0.00% ) (this is with --repeat 100 and the run-to-run variance is bigger than the difference shown) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231120143626.638107480@infradead.org |
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Casey Schaufler
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5f42375904 |
LSM: wireup Linux Security Module syscalls
Wireup lsm_get_self_attr, lsm_set_self_attr and lsm_list_modules system calls. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: linux-api@vger.kernel.org Reviewed-by: Mickaël Salaün <mic@digikod.net> [PM: forward ported beyond v6.6 due merge window changes] Signed-off-by: Paul Moore <paul@paul-moore.com> |
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Linus Torvalds
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5c5e048b24 |
Kbuild updates for v6.7
- Implement the binary search in modpost for faster symbol lookup - Respect HOSTCC when linking host programs written in Rust - Change the binrpm-pkg target to generate kernel-devel RPM package - Fix endianness issues for tee and ishtp MODULE_DEVICE_TABLE - Unify vdso_install rules - Remove unused __memexit* annotations - Eliminate stale whitelisting for __devinit/__devexit from modpost - Enable dummy-tools to handle the -fpatchable-function-entry flag - Add 'userldlibs' syntax -----BEGIN PGP SIGNATURE----- iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAmVFIZgVHG1hc2FoaXJv eUBrZXJuZWwub3JnAAoJED2LAQed4NsGeKwP+wd2kCrxAgS4zPffOcO3cVHfZwJe AXOrTp/v73gzxb9eHXH6TmEDf1Rv7EwW3fmmGJosopJGD6itBqzJa4bNDrbq40rY XStmg0NRmTrIG20CHGgaGWxb8/7WMrYfu0rhFdUXJjmbny6XwJ3US9FvDPC0mZz7 w9VCq5CZOqMsJcQyGkAR7uCHDRzNWiZ/Vnfbz3aa6abFzp7dsjhOgDy5SQ6qZgQz AwHHKNEN+G3HWmGDZqcbV9aDaCk4btnz64h843RAxjy2HNJF360Ohm2KOcdJr5lo DSSStkogBkZNSRQPtqtfknDjzITjeF4JAnUw5ivOtt8ERaO3JRUcr5gHjfw5iV/n o4pC1SXmFzdfoN4dogoYF9rz3j955mSFlT/DSbSbuQS/ELzQs0nsqERxhV4zNCsX KvYPUqKzZLW3i8pHNuhh7z7t4Nbz1zXqUa19FvaLNtFTCtS8/IA868a59S0uqT9I EAIqrNy9qAsk8UuQUxWVx0qf9f5wKGYxW62iMIF9F2lsFRWA8H588CFPUuSU9Bhk KAsvzq249MUGJd0RAjF92EWJgNz/nYzZfFTEL5HKAVauYY5UCyR3AVjrak761I8z ctVskA7eVkaW4eARfcp15Fna15FHVzxBJ3B26oKYIJBQfJLjzZcV8XeMtEcQjEGU jzl+oRqB/Q3oD7Nx =PeX7 -----END PGP SIGNATURE----- Merge tag 'kbuild-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Implement the binary search in modpost for faster symbol lookup - Respect HOSTCC when linking host programs written in Rust - Change the binrpm-pkg target to generate kernel-devel RPM package - Fix endianness issues for tee and ishtp MODULE_DEVICE_TABLE - Unify vdso_install rules - Remove unused __memexit* annotations - Eliminate stale whitelisting for __devinit/__devexit from modpost - Enable dummy-tools to handle the -fpatchable-function-entry flag - Add 'userldlibs' syntax * tag 'kbuild-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits) kbuild: support 'userldlibs' syntax kbuild: dummy-tools: pretend we understand -fpatchable-function-entry kbuild: Correct missing architecture-specific hyphens modpost: squash ALL_{INIT,EXIT}_TEXT_SECTIONS to ALL_TEXT_SECTIONS modpost: merge sectioncheck table entries regarding init/exit sections modpost: use ALL_INIT_SECTIONS for the section check from DATA_SECTIONS modpost: disallow the combination of EXPORT_SYMBOL and __meminit* modpost: remove EXIT_SECTIONS macro modpost: remove MEM_INIT_SECTIONS macro modpost: remove more symbol patterns from the section check whitelist modpost: disallow *driver to reference .meminit* sections linux/init: remove __memexit* annotations modpost: remove ALL_EXIT_DATA_SECTIONS macro kbuild: simplify cmd_ld_multi_m kbuild: avoid too many execution of scripts/pahole-flags.sh kbuild: remove ARCH_POSTLINK from module builds kbuild: unify no-compiler-targets and no-sync-config-targets kbuild: unify vdso_install rules docs: kbuild: add INSTALL_DTBS_PATH UML: remove unused cmd_vdso_install ... |
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Linus Torvalds
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426ee5196d |
sysctl-6.7-rc1
To help make the move of sysctls out of kernel/sysctl.c not incur a size penalty sysctl has been changed to allow us to not require the sentinel, the final empty element on the sysctl array. Joel Granados has been doing all this work. On the v6.6 kernel we got the major infrastructure changes required to support this. For v6.7-rc1 we have all arch/ and drivers/ modified to remove the sentinel. Both arch and driver changes have been on linux-next for a bit less than a month. It is worth re-iterating the value: - this helps reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array - the extra 64-byte penalty is no longer inncurred now when we move sysctls out from kernel/sysctl.c to their own files For v6.8-rc1 expect removal of all the sentinels and also then the unneeded check for procname == NULL. The last 2 patches are fixes recently merged by Krister Johansen which allow us again to use softlockup_panic early on boot. This used to work but the alias work broke it. This is useful for folks who want to detect softlockups super early rather than wait and spend money on cloud solutions with nothing but an eventual hung kernel. Although this hadn't gone through linux-next it's also a stable fix, so we might as well roll through the fixes now. -----BEGIN PGP SIGNATURE----- iQJGBAABCgAwFiEENnNq2KuOejlQLZofziMdCjCSiKcFAmVCqKsSHG1jZ3JvZkBr ZXJuZWwub3JnAAoJEM4jHQowkoinEgYQAIpkqRL85DBwems19Uk9A27lkctwZ6Fc HdslQCObQTsbuKVimZFP4IL2beUfUE0cfLZCXlzp+4nRDOf6vyhyf3w19jPQtI0Q YdqwTk9y6G5VjDsb35QK0+UBloY/kZ1H3/LW4uCwjXTuksUGmWW2Qvey35696Scv hDMLADqKQmdpYxLUaNi9QyYbEAjYtOai2ezg3+i7hTG168t1k/Ab2BxIFrPVsCR2 FAiq05L4ugWjNskdsWBjck05JZsx9SK/qcAxpIPoUm4nGiFNHApXE0E0hs3vsnmn WIHIbxCQw8ZlUDlmw4S+0YH3NFFzFbWfmW8k2b0f2qZTJm/rU4KiJfcJVknkAUVF raFox6XDW0AUQ9L/NOUJ9ip5rup57GcFrMYocdJ3PPAvvmHKOb1D1O741p75RRcc 9j7zwfIRrzjPUqzhsQS/GFjdJu3lJNmEBK1AcgrVry6WoItrAzJHKPPDC7TwaNmD eXpjxMl1sYzzHqtVh4hn+xkUYphj/6gTGMV8zdo+/FopFswgeJW9G8kHtlEWKDPk MRIKwACmfetP6f3ngHunBg+BOipbjCANL7JI0nOhVOQoaULxCCPx+IPJ6GfSyiuH AbcjH8DGI7fJbUkBFoF0dsRFZ2gH8ds1PYMbWUJ6x3FtuCuv5iIuvQYoaWU6itm7 6f0KvCogg0fU =Qf50 -----END PGP SIGNATURE----- Merge tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "To help make the move of sysctls out of kernel/sysctl.c not incur a size penalty sysctl has been changed to allow us to not require the sentinel, the final empty element on the sysctl array. Joel Granados has been doing all this work. On the v6.6 kernel we got the major infrastructure changes required to support this. For v6.7-rc1 we have all arch/ and drivers/ modified to remove the sentinel. Both arch and driver changes have been on linux-next for a bit less than a month. It is worth re-iterating the value: - this helps reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array - the extra 64-byte penalty is no longer inncurred now when we move sysctls out from kernel/sysctl.c to their own files For v6.8-rc1 expect removal of all the sentinels and also then the unneeded check for procname == NULL. The last two patches are fixes recently merged by Krister Johansen which allow us again to use softlockup_panic early on boot. This used to work but the alias work broke it. This is useful for folks who want to detect softlockups super early rather than wait and spend money on cloud solutions with nothing but an eventual hung kernel. Although this hadn't gone through linux-next it's also a stable fix, so we might as well roll through the fixes now" * tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (23 commits) watchdog: move softlockup_panic back to early_param proc: sysctl: prevent aliased sysctls from getting passed to init intel drm: Remove now superfluous sentinel element from ctl_table array Drivers: hv: Remove now superfluous sentinel element from ctl_table array raid: Remove now superfluous sentinel element from ctl_table array fw loader: Remove the now superfluous sentinel element from ctl_table array sgi-xp: Remove the now superfluous sentinel element from ctl_table array vrf: Remove the now superfluous sentinel element from ctl_table array char-misc: Remove the now superfluous sentinel element from ctl_table array infiniband: Remove the now superfluous sentinel element from ctl_table array macintosh: Remove the now superfluous sentinel element from ctl_table array parport: Remove the now superfluous sentinel element from ctl_table array scsi: Remove now superfluous sentinel element from ctl_table array tty: Remove now superfluous sentinel element from ctl_table array xen: Remove now superfluous sentinel element from ctl_table array hpet: Remove now superfluous sentinel element from ctl_table array c-sky: Remove now superfluous sentinel element from ctl_talbe array powerpc: Remove now superfluous sentinel element from ctl_table arrays riscv: Remove now superfluous sentinel element from ctl_table array x86/vdso: Remove now superfluous sentinel element from ctl_table array ... |
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Linus Torvalds
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1e0c505e13 |
asm-generic updates for v6.7
The ia64 architecture gets its well-earned retirement as planned, now that there is one last (mostly) working release that will be maintained as an LTS kernel. The architecture specific system call tables are updated for the added map_shadow_stack() syscall and to remove references to the long-gone sys_lookup_dcookie() syscall. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEiK/NIGsWEZVxh/FrYKtH/8kJUicFAmVC40IACgkQYKtH/8kJ Uidhmw/9EX+aWSXGoObJ3fngaNSMw+PmrEuP8qEKBHxfKHcCdX3hc451Oh4GlhaQ tru91pPwgNvN2/rfoKusxT+V4PemGIzfNni/04rp+P0kvmdw5otQ2yNhsQNsfVmq XGWvkxF4P2GO6bkjjfR/1dDq7GtlyXtwwPDKeLbYb6TnJOZjtx+EAN27kkfSn1Ms R4Sa3zJ+DfHUmHL5S9g+7UD/CZ5GfKNmIskI4Mz5GsfoUz/0iiU+Bge/9sdcdSJQ kmbLy5YnVzfooLZ3TQmBFsO3iAMWb0s/mDdtyhqhTVmTUshLolkPYyKnPFvdupyv shXcpEST2XJNeaDRnL2K4zSCdxdbnCZHDpjfl9wfioBg7I8NfhXKpf1jYZHH1de4 LXq8ndEFEOVQw/zSpYWfQq1sux8Jiqr+UK/ukbVeFWiGGIUs91gEWtPAf8T0AZo9 ujkJvaWGl98O1g5wmBu0/dAR6QcFJMDfVwbmlIFpU8O+MEaz6X8mM+O5/T0IyTcD eMbAUjj4uYcU7ihKzHEv/0SS9Of38kzff67CLN5k8wOP/9NlaGZ78o1bVle9b52A BdhrsAefFiWHp1jT6Y9Rg4HOO/TguQ9e6EWSKOYFulsiLH9LEFaB9RwZLeLytV0W vlAgY9rUW77g1OJcb7DoNv33nRFuxsKqsnz3DEIXtgozo9CzbYI= =H1vH -----END PGP SIGNATURE----- Merge tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull ia64 removal and asm-generic updates from Arnd Bergmann: - The ia64 architecture gets its well-earned retirement as planned, now that there is one last (mostly) working release that will be maintained as an LTS kernel. - The architecture specific system call tables are updated for the added map_shadow_stack() syscall and to remove references to the long-gone sys_lookup_dcookie() syscall. * tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: hexagon: Remove unusable symbols from the ptrace.h uapi asm-generic: Fix spelling of architecture arch: Reserve map_shadow_stack() syscall number for all architectures syscalls: Cleanup references to sys_lookup_dcookie() Documentation: Drop or replace remaining mentions of IA64 lib/raid6: Drop IA64 support Documentation: Drop IA64 from feature descriptions kernel: Drop IA64 support from sig_fault handlers arch: Remove Itanium (IA-64) architecture |
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Linus Torvalds
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ed766c2611 |
Changes to the x86 entry code in v6.7:
- Make IA32_EMULATION boot time configurable with the new ia32_emulation=<bool> boot option. - Clean up fast syscall return validation code: convert it to C and refactor the code. - As part of this, optimize the canonical RIP test code. Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmU9DiARHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1iNAw//cLn9gBXMVPDiCDVUOTqjkZ+OwIF11Y9v WatksSe5hrw0Bzl5CiSvtrWpTkKPnhyM8Lc1WD8l0YSMKprdkQfNAvQOPv0IMLjk XP1pgQhAiXwB87XL/G2sA6RunuK56zlnl7KJiDrQThrS/WOfrq3UkB2vyYEP4GtP 69WZ/WM++u74uEml0+HZ0Z9HVvzwYl1VQPdTYfl52S4H3U8MXL89YEsPr13Ttq88 FMKdXJ/VvItuVM/ZHHqFkGvRJjUtDWePLu29b684Ap6onDJ7uMMw86Gj5UxXtdpB Axsjuwlca8sCPotcqohay6IdyxIth6lMdvjPv0KhA+/QMrHbDaluv88YQs4k7Add 1GPULH6oeDTHxMPOcJmFuSTpMY8HP6O9ZIXB6ogQRkLaDJKaWr5UQU7L2VBQ/WUy NRa6mba0XHYrz6U7DmtsdL0idWBJeJokHmaIcGJ/pp6gMznvufm2+SoJ6w6wcYva VTSTyrAAj/N9/TzJ5i8S2+yDPI9GanFpZJfYbW/rT9XGutvXWVKe3AmUNgR8O+hE JiEMfpR0TtXXlrik74jur/RPZhaFIE8MeCvJrkJ3oxQlPThYSTMBAlUOtD7kOfNT onjPrumREX4hOIBU+nnC9VrJMqxX9lz4xDzqw3jvX99Ma0o8Wx/UndWELX8tAYwd j8M8NWAbv90= =YkaP -----END PGP SIGNATURE----- Merge tag 'x86-entry-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 entry updates from Ingo Molnar: - Make IA32_EMULATION boot time configurable with the new ia32_emulation=<bool> boot option - Clean up fast syscall return validation code: convert it to C and refactor the code - As part of this, optimize the canonical RIP test code * tag 'x86-entry-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry/32: Clean up syscall fast exit tests x86/entry/64: Use TASK_SIZE_MAX for canonical RIP test x86/entry/64: Convert SYSRET validation tests to C x86/entry/32: Remove SEP test for SYSEXIT x86/entry/32: Convert do_fast_syscall_32() to bool return type x86/entry/compat: Combine return value test from syscall handler x86/entry/64: Remove obsolete comment on tracing vs. SYSRET x86: Make IA32_EMULATION boot time configurable x86/entry: Make IA32 syscalls' availability depend on ia32_enabled() x86/elf: Make loading of 32bit processes depend on ia32_enabled() x86/entry: Compile entry_SYSCALL32_ignore() unconditionally x86/entry: Rename ignore_sysret() x86: Introduce ia32_enabled() |