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* Merge branch 'akpm' (patches from Andrew)Linus Torvalds2020-12-151-17/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc updates from Andrew Morton: - a few random little subsystems - almost all of the MM patches which are staged ahead of linux-next material. I'll trickle to post-linux-next work in as the dependents get merged up. Subsystems affected by this patch series: kthread, kbuild, ide, ntfs, ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation, kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction, oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc, uaccess, zram, and cleanups). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits) mm: cleanup kstrto*() usage mm: fix fall-through warnings for Clang mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at mm: shmem: convert shmem_enabled_show to use sysfs_emit_at mm:backing-dev: use sysfs_emit in macro defining functions mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening mm: use sysfs_emit for struct kobject * uses mm: fix kernel-doc markups zram: break the strict dependency from lzo zram: add stat to gather incompressible pages since zram set up zram: support page writeback mm/process_vm_access: remove redundant initialization of iov_r mm/zsmalloc.c: rework the list_add code in insert_zspage() mm/zswap: move to use crypto_acomp API for hardware acceleration mm/zswap: fix passing zero to 'PTR_ERR' warning mm/zswap: make struct kernel_param_ops definitions const userfaultfd/selftests: hint the test runner on required privilege userfaultfd/selftests: fix retval check for userfaultfd_open() userfaultfd/selftests: always dump something in modes userfaultfd: selftests: make __{s,u}64 format specifiers portable ...
| * mm: forbid splitting special mappingsDmitry Safonov2020-12-151-17/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't allow splitting of vm_special_mapping's. It affects vdso/vvar areas. Uprobes have only one page in xol_area so they aren't affected. Those restrictions were enforced by checks in .mremap() callbacks. Restrict resizing with generic .split() callback. Link: https://lkml.kernel.org/r/20201013013416.390574-7-dima@arista.com Signed-off-by: Dmitry Safonov <dima@arista.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'core-entry-2020-12-14' of ↵Linus Torvalds2020-12-143-0/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core entry/exit updates from Thomas Gleixner: "A set of updates for entry/exit handling: - More generalization of entry/exit functionality - The consolidation work to reclaim TIF flags on x86 and also for non-x86 specific TIF flags which are solely relevant for syscall related work and have been moved into their own storage space. The x86 specific part had to be merged in to avoid a major conflict. - The TIF_NOTIFY_SIGNAL work which replaces the inefficient signal delivery mode of task work and results in an impressive performance improvement for io_uring. The non-x86 consolidation of this is going to come seperate via Jens. - The selective syscall redirection facility which provides a clean and efficient way to support the non-Linux syscalls of WINE by catching them at syscall entry and redirecting them to the user space emulation. This can be utilized for other purposes as well and has been designed carefully to avoid overhead for the regular fastpath. This includes the core changes and the x86 support code. - Simplification of the context tracking entry/exit handling for the users of the generic entry code which guarantee the proper ordering and protection. - Preparatory changes to make the generic entry code accomodate S390 specific requirements which are mostly related to their syscall restart mechanism" * tag 'core-entry-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) entry: Add syscall_exit_to_user_mode_work() entry: Add exit_to_user_mode() wrapper entry_Add_enter_from_user_mode_wrapper entry: Rename exit_to_user_mode() entry: Rename enter_from_user_mode() docs: Document Syscall User Dispatch selftests: Add benchmark for syscall user dispatch selftests: Add kselftest for syscall user dispatch entry: Support Syscall User Dispatch on common syscall entry kernel: Implement selective syscall userspace redirection signal: Expose SYS_USER_DISPATCH si_code type x86: vdso: Expose sigreturn address on vdso to the kernel MAINTAINERS: Add entry for common entry code entry: Fix boot for !CONFIG_GENERIC_ENTRY x86: Support HAVE_CONTEXT_TRACKING_OFFSTACK context_tracking: Only define schedule_user() on !HAVE_CONTEXT_TRACKING_OFFSTACK archs sched: Detect call to schedule from critical entry code context_tracking: Don't implement exception_enter/exit() on CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK context_tracking: Introduce HAVE_CONTEXT_TRACKING_OFFSTACK x86: Reclaim unused x86 TI flags ...
| * | x86: vdso: Expose sigreturn address on vdso to the kernelGabriel Krisman Bertazi2020-12-023-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Syscall user redirection requires the signal trampoline code to not be captured, in order to support returning with a locked selector while avoiding recursion back into the signal handler. For ia-32, which has the trampoline in the vDSO, expose the entry points to the kernel, such that it can avoid dispatching syscalls from that region to userspace. Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20201127193238.821364-2-krisman@collabora.com
* | | Merge tag 'x86_cleanups_for_v5.11' of ↵Linus Torvalds2020-12-141-2/+2
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: "Another branch with a nicely negative diffstat, just the way I like 'em: - Remove all uses of TIF_IA32 and TIF_X32 and reclaim the two bits in the end (Gabriel Krisman Bertazi) - All kinds of minor cleanups all over the tree" * tag 'x86_cleanups_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/ia32_signal: Propagate __user annotation properly x86/alternative: Update text_poke_bp() kernel-doc comment x86/PCI: Make a kernel-doc comment a normal one x86/asm: Drop unused RDPID macro x86/boot/compressed/64: Use TEST %reg,%reg instead of CMP $0,%reg x86/head64: Remove duplicate include x86/mm: Declare 'start' variable where it is used x86/head/64: Remove unused GET_CR2_INTO() macro x86/boot: Remove unused finalize_identity_maps() x86/uaccess: Document copy_from_user_nmi() x86/dumpstack: Make show_trace_log_lvl() static x86/mtrr: Fix a kernel-doc markup x86/setup: Remove unused MCA variables x86, libnvdimm/test: Remove COPY_MC_TEST x86: Reclaim TIF_IA32 and TIF_X32 x86/mm: Convert mmu context ia32_compat into a proper flags field x86/elf: Use e_machine to check for x32/ia32 in setup_additional_pages() elf: Expose ELF header on arch_setup_additional_pages() x86/elf: Use e_machine to select start_thread for x32 elf: Expose ELF header in compat_start_thread() ...
| * | x86/elf: Use e_machine to check for x32/ia32 in setup_additional_pages()Gabriel Krisman Bertazi2020-10-261-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since TIF_X32 is going away, avoid using it to find the ELF type when choosing which additional pages to set up. According to SysV AMD64 ABI Draft, an AMD64 ELF object using ILP32 must have ELFCLASS32 with (E_MACHINE == EM_X86_64), so use that ELF field to differentiate a x32 object from a IA32 object when executing setup_additional_pages() in compat mode. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201004032536.1229030-9-krisman@collabora.com
* | x86/vdso: Implement a vDSO for Intel SGX enclave callSean Christopherson2020-11-183-0/+154
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enclaves encounter exceptions for lots of reasons: everything from enclave page faults to NULL pointer dereferences, to system calls that must be “proxied” to the kernel from outside the enclave. In addition to the code contained inside an enclave, there is also supporting code outside the enclave called an “SGX runtime”, which is virtually always implemented inside a shared library. The runtime helps build the enclave and handles things like *re*building the enclave if it got destroyed by something like a suspend/resume cycle. The rebuilding has traditionally been handled in SIGSEGV handlers, registered by the library. But, being process-wide, shared state, signal handling and shared libraries do not mix well. Introduce a vDSO function call that wraps the enclave entry functions (EENTER/ERESUME functions of the ENCLU instruciton) and returns information about any exceptions to the caller in the SGX runtime. Instead of generating a signal, the kernel places exception information in RDI, RSI and RDX. The kernel-provided userspace portion of the vDSO handler will place this information in a user-provided buffer or trigger a user-provided callback at the time of the exception. The vDSO function calling convention uses the standard RDI RSI, RDX, RCX, R8 and R9 registers. This makes it possible to declare the vDSO as a C prototype, but other than that there is no specific support for SystemV ABI. Things like storing XSAVE are the responsibility of the enclave and the runtime. [ bp: Change vsgx.o build dependency to CONFIG_X86_SGX. ] Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Co-developed-by: Cedric Xing <cedric.xing@intel.com> Signed-off-by: Cedric Xing <cedric.xing@intel.com> Co-developed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Jethro Beekman <jethro@fortanix.com> Link: https://lkml.kernel.org/r/20201112220135.165028-20-jarkko@kernel.org
* | x86/vdso: Add support for exception fixup in vDSO functionsSean Christopherson2020-11-185-5/+134
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signals are a horrid little mechanism. They are especially nasty in multi-threaded environments because signal state like handlers is global across the entire process. But, signals are basically the only way that userspace can “gracefully” handle and recover from exceptions. The kernel generally does not like exceptions to occur during execution. But, exceptions are a fact of life and must be handled in some circumstances. The kernel handles them by keeping a list of individual instructions which may cause exceptions. Instead of truly handling the exception and returning to the instruction that caused it, the kernel instead restarts execution at a *different* instruction. This makes it obvious to that thread of execution that the exception occurred and lets *that* code handle the exception instead of the handler. This is not dissimilar to the try/catch exceptions mechanisms that some programming languages have, but applied *very* surgically to single instructions. It effectively changes the visible architecture of the instruction. Problem ======= SGX generates a lot of signals, and the code to enter and exit enclaves and muck with signal handling is truly horrid. At the same time, an approach like kernel exception fixup can not be easily applied to userspace instructions because it changes the visible instruction architecture. Solution ======== The vDSO is a special page of kernel-provided instructions that run in userspace. Any userspace calling into the vDSO knows that it is special. This allows the kernel a place to legitimately rewrite the user/kernel contract and change instruction behavior. Add support for fixing up exceptions that occur while executing in the vDSO. This replaces what could traditionally only be done with signal handling. This new mechanism will be used to replace previously direct use of SGX instructions by userspace. Just introduce the vDSO infrastructure. Later patches will actually replace signal generation with vDSO exception fixup. Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Jethro Beekman <jethro@fortanix.com> Link: https://lkml.kernel.org/r/20201112220135.165028-17-jarkko@kernel.org
* Merge tag 'kbuild-v5.10' of ↵Linus Torvalds2020-10-221-3/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Support 'make compile_commands.json' to generate the compilation database more easily, avoiding stale entries - Support 'make clang-analyzer' and 'make clang-tidy' for static checks using clang-tidy - Preprocess scripts/modules.lds.S to allow CONFIG options in the module linker script - Drop cc-option tests from compiler flags supported by our minimal GCC/Clang versions - Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y - Use sha1 build id for both BFD linker and LLD - Improve deb-pkg for reproducible builds and rootless builds - Remove stale, useless scripts/namespace.pl - Turn -Wreturn-type warning into error - Fix build error of deb-pkg when CONFIG_MODULES=n - Replace 'hostname' command with more portable 'uname -n' - Various Makefile cleanups * tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits) kbuild: Use uname for LINUX_COMPILE_HOST detection kbuild: Only add -fno-var-tracking-assignments for old GCC versions kbuild: remove leftover comment for filechk utility treewide: remove DISABLE_LTO kbuild: deb-pkg: clean up package name variables kbuild: deb-pkg: do not build linux-headers package if CONFIG_MODULES=n kbuild: enforce -Werror=return-type scripts: remove namespace.pl builddeb: Add support for all required debian/rules targets builddeb: Enable rootless builds builddeb: Pass -n to gzip for reproducible packages kbuild: split the build log of kallsyms kbuild: explicitly specify the build id style scripts/setlocalversion: make git describe output more reliable kbuild: remove cc-option test of -Werror=date-time kbuild: remove cc-option test of -fno-stack-check kbuild: remove cc-option test of -fno-strict-overflow kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles kbuild: remove redundant CONFIG_KASAN check from scripts/Makefile.kasan kbuild: do not create built-in objects for external module builds ...
| * treewide: remove DISABLE_LTOSami Tolvanen2020-10-211-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change removes all instances of DISABLE_LTO from Makefiles, as they are currently unused, and the preferred method of disabling LTO is to filter out the flags instead. Note added by Masahiro Yamada: DISABLE_LTO was added as preparation for GCC LTO, but GCC LTO was not pulled into the mainline. (https://lkml.org/lkml/2014/4/8/272) Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
| * kbuild: explicitly specify the build id styleBill Wendling2020-10-091-1/+1
| | | | | | | | | | | | | | | | | | | | ld's --build-id defaults to "sha1" style, while lld defaults to "fast". The build IDs are very different between the two, which may confuse programs that reference them. Signed-off-by: Bill Wendling <morbo@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* | x86/paravirt: Remove 32-bit support from CONFIG_PARAVIRT_XXLJuergen Gross2020-08-151-0/+1
|/ | | | | | | | | | The last 32-bit user of stuff under CONFIG_PARAVIRT_XXL is gone. Remove 32-bit specific parts. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200815100641.26362-2-jgross@suse.com
* Merge tag 'for-linus-5.9-rc1b-tag' of ↵Linus Torvalds2020-08-141-30/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - Remove support for running as 32-bit Xen PV-guest. 32-bit PV guests are rarely used, are lacking security fixes for Meltdown, and can be easily replaced by PVH mode. Another series for doing more cleanup will follow soon (removal of 32-bit-only pvops functionality). - Fixes and additional features for the Xen display frontend driver. * tag 'for-linus-5.9-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: drm/xen-front: Pass dumb buffer data offset to the backend xen: Sync up with the canonical protocol definition in Xen drm/xen-front: Add YUYV to supported formats drm/xen-front: Fix misused IS_ERR_OR_NULL checks xen/gntdev: Fix dmabuf import with non-zero sgt offset x86/xen: drop tests for highmem in pv code x86/xen: eliminate xen-asm_64.S x86/xen: remove 32-bit Xen PV guest support
| * x86/xen: remove 32-bit Xen PV guest supportJuergen Gross2020-08-111-30/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | Xen is requiring 64-bit machines today and since Xen 4.14 it can be built without 32-bit PV guest support. There is no need to carry the burden of 32-bit PV guest support in the kernel any longer, as new guests can be either HVM or PVH, or they can use a 64 bit kernel. Remove the 32-bit Xen PV support from the kernel. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
* | Merge tag 'kbuild-v5.9' of ↵Linus Torvalds2020-08-091-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - run the checker (e.g. sparse) after the compiler - remove unneeded cc-option tests for old compiler flags - fix tar-pkg to install dtbs - introduce ccflags-remove-y and asflags-remove-y syntax - allow to trace functions in sub-directories of lib/ - introduce hostprogs-always-y and userprogs-always-y syntax - various Makefile cleanups * tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled kbuild: introduce hostprogs-always-y and userprogs-always-y kbuild: sort hostprogs before passing it to ifneq kbuild: move host .so build rules to scripts/gcc-plugins/Makefile kbuild: Replace HTTP links with HTTPS ones kbuild: trace functions in subdirectories of lib/ kbuild: introduce ccflags-remove-y and asflags-remove-y kbuild: do not export LDFLAGS_vmlinux kbuild: always create directories of targets powerpc/boot: add DTB to 'targets' kbuild: buildtar: add dtbs support kbuild: remove cc-option test of -ffreestanding kbuild: remove cc-option test of -fno-stack-protector Revert "kbuild: Create directory for target DTB" kbuild: run the checker after the compiler
| * | kbuild: remove cc-option test of -fno-stack-protectorMasahiro Yamada2020-07-071-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some Makefiles already pass -fno-stack-protector unconditionally. For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile. No problem report so far about hard-coding this option. So, we can assume all supported compilers know -fno-stack-protector. GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN) Get rid of cc-option from -fno-stack-protector. Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'. Note: arch/mips/vdso/Makefile adds -fno-stack-protector twice, first unconditionally, and second conditionally. I removed the second one. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
* / timens: make vdso_join_timens() always succeedChristian Brauner2020-07-081-3/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As discussed on-list (cf. [1]), in order to make setns() support time namespaces when attaching to multiple namespaces at once properly we need to tweak vdso_join_timens() to always succeed. So switch vdso_join_timens() to using a read lock and replacing mmap_write_lock_killable() to mmap_read_lock() as we discussed. Last cycle setns() was changed to support attaching to multiple namespaces atomically. This requires all namespaces to have a point of no return where they can't fail anymore. Specifically, <namespace-type>_install() is allowed to perform permission checks and install the namespace into the new struct nsset that it has been given but it is not allowed to make visible changes to the affected task. Once <namespace-type>_install() returns anything that the given namespace type requires to be setup in addition needs to ideally be done in a function that can't fail or if it fails the failure is not fatal. For time namespaces the relevant functions that fall into this category are timens_set_vvar_page() and vdso_join_timens(). Currently the latter can fail but doesn't need to. With this we can go on to implement a timens_commit() helper in a follow up patch to be used by setns(). [1]: https://lore.kernel.org/lkml/20200611110221.pgd3r5qkjrjmfqa2@wittgenstein Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Andrei Vagin <avagin@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Dmitry Safonov <dima@arista.com> Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20200706154912.3248030-2-christian.brauner@ubuntu.com
* Rebase locking/kcsan to locking/urgentThomas Gleixner2020-06-111-0/+6
|\ | | | | | | | | | | | | | | | | | | | | Merge the state of the locking kcsan branch before the read/write_once() and the atomics modifications got merged. Squash the fallout of the rebase on top of the read/write once and atomic fallback work into the merge. The history of the original branch is preserved in tag locking-kcsan-2020-06-02. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * Merge tag 'v5.7-rc1' into locking/kcsan, to resolve conflicts and refreshIngo Molnar2020-04-135-6/+16
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Resolve these conflicts: arch/x86/Kconfig arch/x86/kernel/Makefile Do a minor "evil merge" to move the KCSAN entry up a bit by a few lines in the Kconfig to reduce the probability of future conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * \ Merge branch 'x86/kdump' into locking/kcsan, to resolve conflictsIngo Molnar2020-03-215-7/+132
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/purgatory/Makefile Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | x86/vdso: Enable sanitizers for vma.oJann Horn2020-01-101-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vDSO makefile opts out of all sanitizers (and objtool validation); however, vma.o is a normal kernel object file (and already has objtool validation selectively enabled), so turn the sanitizers back on for that file. Signed-off-by: Jann Horn <jannh@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Marco Elver <elver@google.com> Cc: Paul E. McKenney <paulmck@kernel.org> Link: https://lkml.kernel.org/r/20200106200204.94782-1-jannh@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | Merge tag 'v5.5-rc4' into locking/kcsan, to resolve conflictsIngo Molnar2019-12-303-6/+4
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: init/main.c lib/Kconfig.debug Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | x86, kcsan: Enable KCSAN for x86Marco Elver2019-11-161-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch enables KCSAN for x86, with updates to build rules to not use KCSAN for several incompatible compilation units. Signed-off-by: Marco Elver <elver@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
* | | | | mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse2020-06-091-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | x86/vdso/Makefile: Add vobjs32Dmitry Safonov2020-04-211-10/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Treat ia32/i386 objects in array the same as 64-bit vdso objects. Co-developed-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200420183256.660371-5-dima@arista.com
* | | | | x86/vdso/vdso2c: Convert iterators to unsignedDmitry Safonov2020-04-211-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | `i` and `j` are used everywhere with unsigned types. Convert `i` to unsigned long in order to avoid signed to unsigned comparisons. Convert `k` to unsigned int with the same purpose. Also, drop `j` as `i` could be used in place of it. Introduce syms_nr for readability. Co-developed-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200420183256.660371-4-dima@arista.com
* | | | | x86/vdso/vdso2c: Correct error messages on file openDmitry Safonov2020-04-211-2/+2
| |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | err() message in main() is misleading: it should print `outfilename`, which is argv[3], not argv[2]. Correct error messages to be more precise about what failed and for which file. Co-developed-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200420183256.660371-2-dima@arista.com
* | | | sparc,x86: vdso: remove meaningless undefining CONFIG_OPTIMIZE_INLININGMasahiro Yamada2020-04-071-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The code, #undef CONFIG_OPTIMIZE_INLINING, is not working as expected because <linux/compiler_types.h> is parsed before vclock_gettime.c since 28128c61e08e ("kconfig.h: Include compiler types to avoid missed struct attributes"). Since then, <linux/compiler_types.h> is included really early by using the '-include' option. So, you cannot negate the decision of <linux/compiler_types.h> in this way. You can confirm it by checking the pre-processed code, like this: $ make arch/x86/entry/vdso/vdso32/vclock_gettime.i There is no difference with/without CONFIG_CC_OPTIMIZE_FOR_SIZE. It is about two years since 28128c61e08e. Nobody has reported a problem (or, nobody has even noticed the fact that this code is not working). It is ugly and unreliable to attempt to undefine a CONFIG option from C files, and anyway the inlining heuristic is up to the compiler. Just remove the broken code. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: David Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/20200220110807.32534-1-masahiroy@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | Merge tag 'spdx-5.7-rc1' of ↵Linus Torvalds2020-04-032-0/+2
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments
| * | | | .gitignore: add SPDX License IdentifierMasahiro Yamada2020-03-252-0/+2
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | | Merge branch 'x86-build-for-linus' of ↵Linus Torvalds2020-03-311-0/+7
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 build updates from Ingo Molnar: "A handful of updates: two linker script cleanups and a stock defconfig+allmodconfig bootability fix" * 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Discard .note.gnu.property sections in vDSO x86, vmlinux.lds: Add RUNTIME_DISCARD_EXIT to generic DISCARDS x86/Kconfig: Make CMDLINE_OVERRIDE depend on non-empty CMDLINE
| * | | | x86/vdso: Discard .note.gnu.property sections in vDSOH.J. Lu2020-03-271-0/+7
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the command-line option -mx86-used-note=yes which can also be enabled at binutils build time with: --enable-x86-used-note generate GNU x86 used ISA and feature properties the x86 assembler in binutils 2.32 and above generates a program property note in a note section, .note.gnu.property, to encode used x86 ISAs and features. But kernel linker script only contains a single NOTE segment: PHDRS { text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ note PT_NOTE FLAGS(4); /* PF_R */ eh_frame_hdr 0x6474e550; } The NOTE segment generated by the vDSO linker script is aligned to 4 bytes. But the .note.gnu.property section must be aligned to 8 bytes on x86-64: [hjl@gnu-skx-1 vdso]$ readelf -n vdso64.so Displaying notes found in: .note Owner Data size Description Linux 0x00000004 Unknown note type: (0x00000000) description data: 06 00 00 00 readelf: Warning: note with invalid namesz and/or descsz found at offset 0x20 readelf: Warning: type: 0x78, namesize: 0x00000100, descsize: 0x756e694c, alignment: 8 Since the note.gnu.property section in the vDSO is not checked by the dynamic linker, discard the .note.gnu.property sections in the vDSO. [ bp: Massage. ] Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20200326174314.254662-1-hjl.tools@gmail.com
* | | | Merge tag 'x86-entry-2020-03-30' of ↵Linus Torvalds2020-03-301-0/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 entry code updates from Thomas Gleixner: - Convert the 32bit syscalls to be pt_regs based which removes the requirement to push all 6 potential arguments onto the stack and consolidates the interface with the 64bit variant - The first small portion of the exception and syscall related entry code consolidation which aims to address the recently discovered issues vs. RCU, int3, NMI and some other exceptions which can interrupt any context. The bulk of the changes is still work in progress and aimed for 5.8. - A few lockdep namespace cleanups which have been applied into this branch to keep the prerequisites for the ongoing work confined. * tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) x86/entry: Fix build error x86 with !CONFIG_POSIX_TIMERS lockdep: Rename trace_{hard,soft}{irq_context,irqs_enabled}() lockdep: Rename trace_softirqs_{on,off}() lockdep: Rename trace_hardirq_{enter,exit}() x86/entry: Rename ___preempt_schedule x86: Remove unneeded includes x86/entry: Drop asmlinkage from syscalls x86/entry/32: Enable pt_regs based syscalls x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments x86/entry/32: Rename 32-bit specific syscalls x86/entry/32: Clean up syscall_32.tbl x86/entry: Remove ABI prefixes from functions in syscall tables x86/entry/64: Add __SYSCALL_COMMON() x86/entry: Remove syscall qualifier support x86/entry/64: Remove ptregs qualifier from syscall table x86/entry: Move max syscall number calculation to syscallhdr.sh x86/entry/64: Split X32 syscall table into its own file x86/entry/64: Move sys_ni_syscall stub to common.c x86/entry/64: Use syscall wrappers for x32_rt_sigreturn x86/entry: Refactor SYS_NI macros ...
| * | | | x86/entry: Move max syscall number calculation to syscallhdr.shBrian Gerst2020-03-211-0/+1
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of using an array in asm-offsets to calculate the max syscall number, calculate it when writing out the syscall headers. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200313195144.164260-9-brgerst@gmail.com
* | | | x86/vdso: Use generic VDSO clock mode storageThomas Gleixner2020-02-171-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch to the generic VDSO clock mode storage. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts) Acked-by: Juergen Gross <jgross@suse.com> (Xen parts) Acked-by: Paolo Bonzini <pbonzini@redhat.com> (KVM parts) Link: https://lkml.kernel.org/r/20200207124403.152039903@linutronix.de
* | | | x86/vdso: Move VDSO clocksource state tracking to callbackThomas Gleixner2020-02-171-0/+4
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All architectures which use the generic VDSO code have their own storage for the VDSO clock mode. That's pointless and just requires duplicate code. X86 abuses the function which retrieves the architecture specific clock mode storage to mark the clocksource as used in the VDSO. That's silly because this is invoked on every tick when the VDSO data is updated. Move this functionality to the clocksource::enable() callback so it gets invoked once when the clocksource is installed. This allows to make the clock mode storage generic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Michael Kelley <mikelley@microsoft.com> (Hyper-V parts) Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts) Acked-by: Juergen Gross <jgross@suse.com> (Xen parts) Link: https://lkml.kernel.org/r/20200207124402.934519777@linutronix.de
* | | kbuild: rename hostprogs-y/always to hostprogs/always-yMasahiro Yamada2020-02-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In old days, the "host-progs" syntax was used for specifying host programs. It was renamed to the current "hostprogs-y" in 2004. It is typically useful in scripts/Makefile because it allows Kbuild to selectively compile host programs based on the kernel configuration. This commit renames like follows: always -> always-y hostprogs-y -> hostprogs So, scripts/Makefile will look like this: always-$(CONFIG_BUILD_BIN2C) += ... always-$(CONFIG_KALLSYMS) += ... ... hostprogs := $(always-y) $(always-m) I think this makes more sense because a host program is always a host program, irrespective of the kernel configuration. We want to specify which ones to compile by CONFIG options, so always-y will be handier. The "always", "hostprogs-y", "hostprogs-m" will be kept for backward compatibility for a while. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* | | Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds2020-01-281-0/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups all around the map" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU/AMD: Remove amd_get_topology_early() x86/tsc: Remove redundant assignment x86/crash: Use resource_size() x86/cpu: Add a missing prototype for arch_smt_update() x86/nospec: Remove unused RSB_FILL_LOOPS x86/vdso: Provide missing include file x86/Kconfig: Correct spelling and punctuation Documentation/x86/boot: Fix typo x86/boot: Fix a comment's incorrect file reference x86/process: Remove set but not used variables prev and next x86/Kconfig: Fix Kconfig indentation
| * | | x86/vdso: Provide missing include fileValdis Klētnieks2019-12-291-0/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building with C=1, sparse issues a warning: CHECK arch/x86/entry/vdso/vdso32-setup.c arch/x86/entry/vdso/vdso32-setup.c:28:28: warning: symbol 'vdso32_enabled' was not declared. Should it be static? Provide the missing header file. Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/36224.1575599767@turing-police
* | | x86/vdso: Zap vvar pages when switching to a time namespaceDmitry Safonov2020-01-141-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The VVAR page layout depends on whether a task belongs to the root or non-root time namespace. Whenever a task changes its namespace, the VVAR page tables are cleared and then they will be re-faulted with a corresponding layout. Co-developed-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-27-dima@arista.com
* | | x86/vdso: On timens page fault prefault also VVAR pageDmitry Safonov2020-01-141-1/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As timens page has offsets to data on VVAR page VVAR is going to be accessed shortly. Set it up with timens in one page fault as optimization. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Co-developed-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-26-dima@arista.com
* | | x86/vdso: Handle faults on timens pageDmitry Safonov2020-01-141-2/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. Co-developed-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-25-dima@arista.com
* | | x86/vdso: Add time napespace pageDmitry Safonov2020-01-142-2/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To support time namespaces in the VDSO with a minimal impact on regular non time namespace affected tasks, the namespace handling needs to be hidden in a slow path. The most obvious place is vdso_seq_begin(). If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. That page has vdso_data->seq set to 1 to enforce the slow path and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time namespace handling path. The extra check in the case that vdso_data->seq is odd, e.g. a concurrent update of the VDSO data is in progress, is not really affecting regular tasks which are not part of a time namespace as the task is spin waiting for the update to finish and vdso_data->seq to become even again. If a time namespace task hits that code path, it invokes the corresponding time getter function which retrieves the real VVAR page, reads host time and then adds the offset for the requested clock which is stored in the special VVAR page. Allocate the time namespace page among VVAR pages and place vdso_data on it. Provide __arch_get_timens_vdso_data() helper for VDSO code to get the code-relative position of VVARs on that special page. Co-developed-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-23-dima@arista.com
* | | x86/vdso: Provide vdso_data offset on vvar_pageDmitry Safonov2020-01-142-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | VDSO support for time namespaces needs to set up a page with the same layout as VVAR. That timens page will be placed on position of VVAR page inside namespace. That page has vdso_data->seq set to 1 to enforce the slow path and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time namespace handling path. To prepare the time namespace page the kernel needs to know the vdso_data offset. Provide arch_get_vdso_data() helper for locating vdso_data on VVAR page. Co-developed-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-22-dima@arista.com
* | | x86/vdso: Restrict splitting VVAR VMADmitry Safonov2020-01-141-0/+13
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Forbid splitting VVAR VMA resulting in a stricter ABI and reducing the amount of corner-cases to consider while working further on VDSO time namespace support. As the offset from timens to VVAR page is computed compile-time, the pages in VVAR should stay together and not being partically mremap()'ed. Co-developed-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-20-dima@arista.com
* | Merge tag 'y2038-cleanups-5.5' of ↵Linus Torvalds2019-12-011-3/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground Pull y2038 cleanups from Arnd Bergmann: "y2038 syscall implementation cleanups This is a series of cleanups for the y2038 work, mostly intended for namespace cleaning: the kernel defines the traditional time_t, timeval and timespec types that often lead to y2038-unsafe code. Even though the unsafe usage is mostly gone from the kernel, having the types and associated functions around means that we can still grow new users, and that we may be missing conversions to safe types that actually matter. There are still a number of driver specific patches needed to get the last users of these types removed, those have been submitted to the respective maintainers" Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/ * tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits) y2038: alarm: fix half-second cut-off y2038: ipc: fix x32 ABI breakage y2038: fix typo in powerpc vdso "LOPART" y2038: allow disabling time32 system calls y2038: itimer: change implementation to timespec64 y2038: move itimer reset into itimer.c y2038: use compat_{get,set}_itimer on alpha y2038: itimer: compat handling to itimer.c y2038: time: avoid timespec usage in settimeofday() y2038: timerfd: Use timespec64 internally y2038: elfcore: Use __kernel_old_timeval for process times y2038: make ns_to_compat_timeval use __kernel_old_timeval y2038: socket: use __kernel_old_timespec instead of timespec y2038: socket: remove timespec reference in timestamping y2038: syscalls: change remaining timeval to __kernel_old_timeval y2038: rusage: use __kernel_old_timeval y2038: uapi: change __kernel_time_t to __kernel_old_time_t y2038: stat: avoid 'time_t' in 'struct stat' y2038: ipc: remove __kernel_time_t reference from headers y2038: vdso: powerpc: avoid timespec references ...
| * | y2038: vdso: change time_t to __kernel_old_time_tArnd Bergmann2019-11-151-3/+3
| |/ | | | | | | | | | | | | | | | | Only x86 uses the 'time' syscall in vdso, so change that to __kernel_old_time_t as a preparation for removing 'time_t' and '__kernel_time_t' later. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | Merge branch 'x86/build' into x86/asm, to pick up completed topic branchIngo Molnar2019-11-251-2/+0
|\ \ | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.oMasahiro Yamada2019-11-151-2/+0
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CFLAGS_REMOVE_*.o syntax is used to drop particular flags when building objects from C files. It has no effect for assembly files. vdso-note.o is compiled from the assembly file, vdso-note.S, hence CFLAGS_REMOVE_vdso-note.o is meaningless. Neither vvar.c nor vvar.S is found in the vdso directory. Since there is no source file to create vvar.o, CFLAGS_REMOVE_vvar.o is also meaningless. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191114154922.30365-1-yamada.masahiro@socionext.com
* / x86/asm: Use SYM_INNER_LABEL instead of GLOBALJiri Slaby2019-10-181-1/+1
|/ | | | | | | | | | | | | | | | | | | | The GLOBAL macro had several meanings and is going away. Convert all the inner function labels marked with GLOBAL to use SYM_INNER_LABEL instead. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-arch@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191011115108.12392-18-jslaby@suse.cz
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