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2021-09-22KVM: x86: Handle SRCU initialization failure during page track initHaimin Zhang3-4/+9
Check the return of init_srcu_struct(), which can fail due to OOM, when initializing the page track mechanism. Lack of checking leads to a NULL pointer deref found by a modified syzkaller. Reported-by: TCS Robot <tcs_robot@tencent.com> Signed-off-by: Haimin Zhang <tcs_kernel@tencent.com> Message-Id: <1630636626-12262-1-git-send-email-tcs_kernel@tencent.com> [Move the call towards the beginning of kvm_arch_init_vm. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-22KVM: VMX: Remove defunct "nr_active_uret_msrs" fieldSean Christopherson1-4/+0
Remove vcpu_vmx.nr_active_uret_msrs and its associated comment, which are both defunct now that KVM keeps the list constant and instead explicitly tracks which entries need to be loaded into hardware. No functional change intended. Fixes: ee9d22e08d13 ("KVM: VMX: Use flag to indicate "active" uret MSRs instead of sorting list") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210908002401.1947049-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-22KVM: x86: Clear KVM's cached guest CR3 at RESET/INITSean Christopherson1-0/+3
Explicitly zero the guest's CR3 and mark it available+dirty at RESET/INIT. Per Intel's SDM and AMD's APM, CR3 is zeroed at both RESET and INIT. For RESET, this is a nop as vcpu is zero-allocated. For INIT, the bug has likely escaped notice because no firmware/kernel puts its page tables root at PA=0, let alone relies on INIT to get the desired CR3 for such page tables. Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210921000303.400537-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-22KVM: x86: Mark all registers as avail/dirty at vCPU creationSean Christopherson1-0/+2
Mark all registers as available and dirty at vCPU creation, as the vCPU has obviously not been loaded into hardware, let alone been given the chance to be modified in hardware. On SVM, reading from "uninitialized" hardware is a non-issue as VMCBs are zero allocated (thus not truly uninitialized) and hardware does not allow for arbitrary field encoding schemes. On VMX, backing memory for VMCSes is also zero allocated, but true initialization of the VMCS _technically_ requires VMWRITEs, as the VMX architectural specification technically allows CPU implementations to encode fields with arbitrary schemes. E.g. a CPU could theoretically store the inverted value of every field, which would result in VMREAD to a zero-allocated field returns all ones. In practice, only the AR_BYTES fields are known to be manipulated by hardware during VMREAD/VMREAD; no known hardware or VMM (for nested VMX) does fancy encoding of cacheable field values (CR0, CR3, CR4, etc...). In other words, this is technically a bug fix, but practically speakings it's a glorified nop. Failure to mark registers as available has been a lurking bug for quite some time. The original register caching supported only GPRs (+RIP, which is kinda sorta a GPR), with the masks initialized at ->vcpu_reset(). That worked because the two cacheable registers, RIP and RSP, are generally speaking not read as side effects in other flows. Arguably, commit aff48baa34c0 ("KVM: Fetch guest cr3 from hardware on demand") was the first instance of failure to mark regs available. While _just_ marking CR3 available during vCPU creation wouldn't have fixed the VMREAD from an uninitialized VMCS bug because ept_update_paging_mode_cr0() unconditionally read vmcs.GUEST_CR3, marking CR3 _and_ intentionally not reading GUEST_CR3 when it's available would have avoided VMREAD to a technically-uninitialized VMCS. Fixes: aff48baa34c0 ("KVM: Fetch guest cr3 from hardware on demand") Fixes: 6de4f3ada40b ("KVM: Cache pdptrs") Fixes: 6de12732c42c ("KVM: VMX: Optimize vmx_get_rflags()") Fixes: 2fb92db1ec08 ("KVM: VMX: Cache vmcs segment fields") Fixes: bd31fe495d0d ("KVM: VMX: Add proper cache tracking for CR0") Fixes: f98c1e77127d ("KVM: VMX: Add proper cache tracking for CR4") Fixes: 5addc235199f ("KVM: VMX: Cache vmcs.EXIT_QUALIFICATION using arch avail_reg flags") Fixes: 8791585837f6 ("KVM: VMX: Cache vmcs.EXIT_INTR_INFO using arch avail_reg flags") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210921000303.400537-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-19Merge tag 'x86_urgent_for_v5.15_rc2' of ↵Linus Torvalds4-15/+46
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Prevent a infinite loop in the MCE recovery on return to user space, which was caused by a second MCE queueing work for the same page and thereby creating a circular work list. - Make kern_addr_valid() handle existing PMD entries, which are marked not present in the higher level page table, correctly instead of blindly dereferencing them. - Pass a valid address to sanitize_phys(). This was caused by the mixture of inclusive and exclusive ranges. memtype_reserve() expect 'end' being exclusive, but sanitize_phys() wants it inclusive. This worked so far, but with end being the end of the physical address space the fail is exposed. - Increase the maximum supported GPIO numbers for 64bit. Newer SoCs exceed the previous maximum. * tag 'x86_urgent_for_v5.15_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Avoid infinite loop for copy from user recovery x86/mm: Fix kern_addr_valid() to cope with existing but not present entries x86/platform: Increase maximum GPIO number for X86_64 x86/pat: Pass valid address to sanitize_phys()
2021-09-19Merge tag 'kbuild-fixes-v5.15' of ↵Linus Torvalds1-3/+9
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - Fix bugs in checkkconfigsymbols.py - Fix missing sys import in gen_compile_commands.py - Fix missing FORCE warning for ARCH=sh builds - Fix -Wignored-optimization-argument warnings for Clang builds - Turn -Wignored-optimization-argument into an error in order to stop building instead of sprinkling warnings * tag 'kbuild-fixes-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: Add -Werror=ignored-optimization-argument to CLANG_FLAGS x86/build: Do not add -falign flags unconditionally for clang kbuild: Fix comment typo in scripts/Makefile.modpost sh: Add missing FORCE prerequisites in Makefile gen_compile_commands: fix missing 'sys' package checkkconfigsymbols.py: Remove skipping of help lines in parse_kconfig_file checkkconfigsymbols.py: Forbid passing 'HEAD' to --commit
2021-09-19x86/build: Do not add -falign flags unconditionally for clangNathan Chancellor1-3/+9
clang does not support -falign-jumps and only recently gained support for -falign-loops. When one of the configuration options that adds these flags is enabled, clang warns and all cc-{disable-warning,option} that follow fail because -Werror gets added to test for the presence of this warning: clang-14: warning: optimization flag '-falign-jumps=0' is not supported [-Wignored-optimization-argument] To resolve this, add a couple of cc-option calls when building with clang; gcc has supported these options since 3.2 so there is no point in testing for their support. -falign-functions was implemented in clang-7, -falign-loops was implemented in clang-14, and -falign-jumps has not been implemented yet. Link: https://lore.kernel.org/r/YSQE2f5teuvKLkON@Ryzen-9-3900X.localdomain/ Link: https://lore.kernel.org/r/20210824022640.2170859-2-nathan@kernel.org/ Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-09-17Merge tag 'for-linus-5.15b-rc2-tag' of ↵Linus Torvalds2-2/+12
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - The first hunk of a Xen swiotlb fixup series fixing multiple minor issues and doing some small cleanups - Some further Xen related fixes avoiding WARN() splats when running as Xen guests or dom0 - A Kconfig fix allowing the pvcalls frontend to be built as a module * tag 'for-linus-5.15b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: swiotlb-xen: drop DEFAULT_NSLABS swiotlb-xen: arrange to have buffer info logged swiotlb-xen: drop leftover __ref swiotlb-xen: limit init retries swiotlb-xen: suppress certain init retries swiotlb-xen: maintain slab count properly swiotlb-xen: fix late init retry swiotlb-xen: avoid double free xen/pvcalls: backend can be a module xen: fix usage of pmd_populate in mremap for pv guests xen: reset legacy rtc flag for PV domU PM: base: power: don't try to use non-existing RTC for storing data xen/balloon: use a kernel thread instead a workqueue
2021-09-15Merge tag 'hyperv-fixes-signed-20210915' of ↵Linus Torvalds1-17/+26
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - Fix kernel crash caused by uio driver (Vitaly Kuznetsov) - Remove on-stack cpumask from HV APIC code (Wei Liu) * tag 'hyperv-fixes-signed-20210915' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: remove on-stack cpumask from hv_send_ipi_mask_allbutself asm-generic/hyperv: provide cpumask_to_vpset_noself Drivers: hv: vmbus: Fix kernel crash upon unbinding a device from uio_hv_generic driver
2021-09-15xen: fix usage of pmd_populate in mremap for pv guestsJuergen Gross1-2/+5
Commit 0881ace292b662 ("mm/mremap: use pmd/pud_poplulate to update page table entries") introduced a regression when running as Xen PV guest. Today pmd_populate() for Xen PV assumes that the PFN inserted is referencing a not yet used page table. In case of move_normal_pmd() this is not true, resulting in WARN splats like: [34321.304270] ------------[ cut here ]------------ [34321.304277] WARNING: CPU: 0 PID: 23628 at arch/x86/xen/multicalls.c:102 xen_mc_flush+0x176/0x1a0 [34321.304288] Modules linked in: [34321.304291] CPU: 0 PID: 23628 Comm: apt-get Not tainted 5.14.1-20210906-doflr-mac80211debug+ #1 [34321.304294] Hardware name: MSI MS-7640/890FXA-GD70 (MS-7640) , BIOS V1.8B1 09/13/2010 [34321.304296] RIP: e030:xen_mc_flush+0x176/0x1a0 [34321.304300] Code: 89 45 18 48 c1 e9 3f 48 89 ce e9 20 ff ff ff e8 60 03 00 00 66 90 5b 5d 41 5c 41 5d c3 48 c7 45 18 ea ff ff ff be 01 00 00 00 <0f> 0b 8b 55 00 48 c7 c7 10 97 aa 82 31 db 49 c7 c5 38 97 aa 82 65 [34321.304303] RSP: e02b:ffffc90000a97c90 EFLAGS: 00010002 [34321.304305] RAX: ffff88807d416398 RBX: ffff88807d416350 RCX: ffff88807d416398 [34321.304306] RDX: 0000000000000001 RSI: 0000000000000001 RDI: deadbeefdeadf00d [34321.304308] RBP: ffff88807d416300 R08: aaaaaaaaaaaaaaaa R09: ffff888006160cc0 [34321.304309] R10: deadbeefdeadf00d R11: ffffea000026a600 R12: 0000000000000000 [34321.304310] R13: ffff888012f6b000 R14: 0000000012f6b000 R15: 0000000000000001 [34321.304320] FS: 00007f5071177800(0000) GS:ffff88807d400000(0000) knlGS:0000000000000000 [34321.304322] CS: 10000e030 DS: 0000 ES: 0000 CR0: 0000000080050033 [34321.304323] CR2: 00007f506f542000 CR3: 00000000160cc000 CR4: 0000000000000660 [34321.304326] Call Trace: [34321.304331] xen_alloc_pte+0x294/0x320 [34321.304334] move_pgt_entry+0x165/0x4b0 [34321.304339] move_page_tables+0x6fa/0x8d0 [34321.304342] move_vma.isra.44+0x138/0x500 [34321.304345] __x64_sys_mremap+0x296/0x410 [34321.304348] do_syscall_64+0x3a/0x80 [34321.304352] entry_SYSCALL_64_after_hwframe+0x44/0xae [34321.304355] RIP: 0033:0x7f507196301a [34321.304358] Code: 73 01 c3 48 8b 0d 76 0e 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 19 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 46 0e 0c 00 f7 d8 64 89 01 48 [34321.304360] RSP: 002b:00007ffda1eecd38 EFLAGS: 00000246 ORIG_RAX: 0000000000000019 [34321.304362] RAX: ffffffffffffffda RBX: 000056205f950f30 RCX: 00007f507196301a [34321.304363] RDX: 0000000001a00000 RSI: 0000000001900000 RDI: 00007f506dc56000 [34321.304364] RBP: 0000000001a00000 R08: 0000000000000010 R09: 0000000000000004 [34321.304365] R10: 0000000000000001 R11: 0000000000000246 R12: 00007f506dc56060 [34321.304367] R13: 00007f506dc56000 R14: 00007f506dc56060 R15: 000056205f950f30 [34321.304368] ---[ end trace a19885b78fe8f33e ]--- [34321.304370] 1 of 2 multicall(s) failed: cpu 0 [34321.304371] call 2: op=12297829382473034410 arg=[aaaaaaaaaaaaaaaa] result=-22 Fix that by modifying xen_alloc_ptpage() to only pin the page table in case it wasn't pinned already. Fixes: 0881ace292b662 ("mm/mremap: use pmd/pud_poplulate to update page table entries") Cc: <stable@vger.kernel.org> Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20210908073640.11299-1-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2021-09-15xen: reset legacy rtc flag for PV domUJuergen Gross1-0/+7
A Xen PV guest doesn't have a legacy RTC device, so reset the legacy RTC flag. Otherwise the following WARN splat will occur at boot: [ 1.333404] WARNING: CPU: 1 PID: 1 at /home/gross/linux/head/drivers/rtc/rtc-mc146818-lib.c:25 mc146818_get_time+0x1be/0x210 [ 1.333404] Modules linked in: [ 1.333404] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 5.14.0-rc7-default+ #282 [ 1.333404] RIP: e030:mc146818_get_time+0x1be/0x210 [ 1.333404] Code: c0 64 01 c5 83 fd 45 89 6b 14 7f 06 83 c5 64 89 6b 14 41 83 ec 01 b8 02 00 00 00 44 89 63 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 <0f> 0b 48 c7 c7 30 0e ef 82 4c 89 e6 e8 71 2a 24 00 48 c7 c0 ff ff [ 1.333404] RSP: e02b:ffffc90040093df8 EFLAGS: 00010002 [ 1.333404] RAX: 00000000000000ff RBX: ffffc90040093e34 RCX: 0000000000000000 [ 1.333404] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000000000d [ 1.333404] RBP: ffffffff82ef0e30 R08: ffff888005013e60 R09: 0000000000000000 [ 1.333404] R10: ffffffff82373e9b R11: 0000000000033080 R12: 0000000000000200 [ 1.333404] R13: 0000000000000000 R14: 0000000000000002 R15: ffffffff82cdc6d4 [ 1.333404] FS: 0000000000000000(0000) GS:ffff88807d440000(0000) knlGS:0000000000000000 [ 1.333404] CS: 10000e030 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.333404] CR2: 0000000000000000 CR3: 000000000260a000 CR4: 0000000000050660 [ 1.333404] Call Trace: [ 1.333404] ? wakeup_sources_sysfs_init+0x30/0x30 [ 1.333404] ? rdinit_setup+0x2b/0x2b [ 1.333404] early_resume_init+0x23/0xa4 [ 1.333404] ? cn_proc_init+0x36/0x36 [ 1.333404] do_one_initcall+0x3e/0x200 [ 1.333404] kernel_init_freeable+0x232/0x28e [ 1.333404] ? rest_init+0xd0/0xd0 [ 1.333404] kernel_init+0x16/0x120 [ 1.333404] ret_from_fork+0x1f/0x30 Cc: <stable@vger.kernel.org> Fixes: 8d152e7a5c7537 ("x86/rtc: Replace paravirt rtc check with platform legacy quirk") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210903084937.19392-3-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2021-09-14memblock: introduce saner 'memblock_free_ptr()' interfaceLinus Torvalds4-8/+5
The boot-time allocation interface for memblock is a mess, with 'memblock_alloc()' returning a virtual pointer, but then you are supposed to free it with 'memblock_free()' that takes a _physical_ address. Not only is that all kinds of strange and illogical, but it actually causes bugs, when people then use it like a normal allocation function, and it fails spectacularly on a NULL pointer: https://lore.kernel.org/all/20210912140820.GD25450@xsang-OptiPlex-9020/ or just random memory corruption if the debug checks don't catch it: https://lore.kernel.org/all/61ab2d0c-3313-aaab-514c-e15b7aa054a0@suse.cz/ I really don't want to apply patches that treat the symptoms, when the fundamental cause is this horribly confusing interface. I started out looking at just automating a sane replacement sequence, but because of this mix or virtual and physical addresses, and because people have used the "__pa()" macro that can take either a regular kernel pointer, or just the raw "unsigned long" address, it's all quite messy. So this just introduces a new saner interface for freeing a virtual address that was allocated using 'memblock_alloc()', and that was kept as a regular kernel pointer. And then it converts a couple of users that are obvious and easy to test, including the 'xbc_nodes' case in lib/bootconfig.c that caused problems. Reported-by: kernel test robot <oliver.sang@intel.com> Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed") Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-14x86/mce: Avoid infinite loop for copy from user recoveryTony Luck1-11/+32
There are two cases for machine check recovery: 1) The machine check was triggered by ring3 (application) code. This is the simpler case. The machine check handler simply queues work to be executed on return to user. That code unmaps the page from all users and arranges to send a SIGBUS to the task that triggered the poison. 2) The machine check was triggered in kernel code that is covered by an exception table entry. In this case the machine check handler still queues a work entry to unmap the page, etc. but this will not be called right away because the #MC handler returns to the fix up code address in the exception table entry. Problems occur if the kernel triggers another machine check before the return to user processes the first queued work item. Specifically, the work is queued using the ->mce_kill_me callback structure in the task struct for the current thread. Attempting to queue a second work item using this same callback results in a loop in the linked list of work functions to call. So when the kernel does return to user, it enters an infinite loop processing the same entry for ever. There are some legitimate scenarios where the kernel may take a second machine check before returning to the user. 1) Some code (e.g. futex) first tries a get_user() with page faults disabled. If this fails, the code retries with page faults enabled expecting that this will resolve the page fault. 2) Copy from user code retries a copy in byte-at-time mode to check whether any additional bytes can be copied. On the other side of the fence are some bad drivers that do not check the return value from individual get_user() calls and may access multiple user addresses without noticing that some/all calls have failed. Fix by adding a counter (current->mce_count) to keep track of repeated machine checks before task_work() is called. First machine check saves the address information and calls task_work_add(). Subsequent machine checks before that task_work call back is executed check that the address is in the same page as the first machine check (since the callback will offline exactly one page). Expected worst case is four machine checks before moving on (e.g. one user access with page faults disabled, then a repeat to the same address with page faults enabled ... repeat in copy tail bytes). Just in case there is some code that loops forever enforce a limit of 10. [ bp: Massage commit message, drop noinstr, fix typo, extend panic messages. ] Fixes: 5567d11c21a1 ("x86/mce: Send #MC singal from task work") Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/YT/IJ9ziLqmtqEPu@agluck-desk2.amr.corp.intel.com
2021-09-13x86/uaccess: Fix 32-bit __get_user_asm_u64() when CC_HAS_ASM_GOTO_OUTPUT=yWill Deacon1-2/+2
Commit 865c50e1d279 ("x86/uaccess: utilize CONFIG_CC_HAS_ASM_GOTO_OUTPUT") added an optimised version of __get_user_asm() for x86 using 'asm goto'. Like the non-optimised code, the 32-bit implementation of 64-bit get_user() expands to a pair of 32-bit accesses. Unlike the non-optimised code, the _original_ pointer is incremented to copy the high word instead of loading through a new pointer explicitly constructed to point at a 32-bit type. Consequently, if the pointer points at a 64-bit type then we end up loading the wrong data for the upper 32-bits. This was observed as a mount() failure in Android targeting i686 after b0cfcdd9b967 ("d_path: make 'prepend()' fill up the buffer exactly on overflow") because the call to copy_from_kernel_nofault() from prepend_copy() ends up in __get_kernel_nofault() and casts the source pointer to a 'u64 __user *'. An attempt to mount at "/debug_ramdisk" therefore ends up failing trying to mount "/debumdismdisk". Use the existing '__gu_ptr' source pointer to unsigned int for 32-bit __get_user_asm_u64() instead of the original pointer. Cc: Bill Wendling <morbo@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 865c50e1d279 ("x86/uaccess: utilize CONFIG_CC_HAS_ASM_GOTO_OUTPUT") Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-11x86/hyperv: remove on-stack cpumask from hv_send_ipi_mask_allbutselfWei Liu1-17/+26
It is not a good practice to allocate a cpumask on stack, given it may consume up to 1 kilobytes of stack space if the kernel is configured to have 8192 cpus. The internal helper functions __send_ipi_mask{,_ex} need to loop over the provided mask anyway, so it is not too difficult to skip `self' there. We can thus do away with the on-stack cpumask in hv_send_ipi_mask_allbutself. Adjust call sites of __send_ipi_mask as needed. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Suggested-by: Michael Kelley <mikelley@microsoft.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Fixes: 68bb7bfb7985d ("X86/Hyper-V: Enable IPI enlightenments") Signed-off-by: Wei Liu <wei.liu@kernel.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20210910185714.299411-3-wei.liu@kernel.org
2021-09-11Merge branch 'linus' into smp/urgentThomas Gleixner87-1617/+1309
Ensure that all usage sites of get/put_online_cpus() except for the struggler in drivers/thermal are gone. So the last user and the deprecated inlines can be removed.
2021-09-09Merge tag 'for-linus-5.15-rc1' of ↵Linus Torvalds3-2/+25
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML updates from Richard Weinberger: - Support for VMAP_STACK - Support for splice_write in hostfs - Fixes for virt-pci - Fixes for virtio_uml - Various fixes * tag 'for-linus-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: fix stub location calculation um: virt-pci: fix uapi documentation um: enable VMAP_STACK um: virt-pci: don't do DMA from stack hostfs: support splice_write um: virtio_uml: fix memory leak on init failures um: virtio_uml: include linux/virtio-uml.h lib/logic_iomem: fix sparse warnings um: make PCI emulation driver init/exit static
2021-09-08arch: remove compat_alloc_user_spaceArnd Bergmann2-20/+0
All users of compat_alloc_user_space() and copy_in_user() have been removed from the kernel, only a few functions in sparc remain that can be changed to calling arch_copy_in_user() instead. Link: https://lkml.kernel.org/r/20210727144859.4150043-7-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08compat: remove some compat entry pointsArnd Bergmann2-3/+3
These are all handled correctly when calling the native system call entry point, so remove the special cases. Link: https://lkml.kernel.org/r/20210727144859.4150043-6-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08Merge branch 'akpm' (patches from Andrew)Linus Torvalds4-6/+2
Merge more updates from Andrew Morton: "147 patches, based on 7d2a07b769330c34b4deabeed939325c77a7ec2f. Subsystems affected by this patch series: mm (memory-hotplug, rmap, ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan), alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib, checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig, selftests, ipc, and scripts" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits) scripts: check_extable: fix typo in user error message mm/workingset: correct kernel-doc notations ipc: replace costly bailout check in sysvipc_find_ipc() selftests/memfd: remove unused variable Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH configs: remove the obsolete CONFIG_INPUT_POLLDEV prctl: allow to setup brk for et_dyn executables pid: cleanup the stale comment mentioning pidmap_init(). kernel/fork.c: unexport get_{mm,task}_exe_file coredump: fix memleak in dump_vma_snapshot() fs/coredump.c: log if a core dump is aborted due to changed file permissions nilfs2: use refcount_dec_and_lock() to fix potential UAF nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group nilfs2: fix NULL pointer in nilfs_##name##_attr_release nilfs2: fix memory leak in nilfs_sysfs_create_device_group trap: cleanup trap_init() init: move usermodehelper_enable() to populate_rootfs() ...
2021-09-08x86/mm: Fix kern_addr_valid() to cope with existing but not present entriesMike Rapoport1-3/+3
Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ #508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aefc1d28 ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a7818c ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org
2021-09-08configs: remove the obsolete CONFIG_INPUT_POLLDEVZenghui Yu2-2/+0
This CONFIG option was removed in commit 278b13ce3a89 ("Input: remove input_polled_dev implementation") so there's no point to keep it in defconfigs any longer. Get rid of the leftover for all arches. Link: https://lkml.kernel.org/r/20210726074741.1062-1-yuzenghui@huawei.com Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08mm/memory_hotplug: remove nid parameter from arch_remove_memory()David Hildenbrand2-4/+2
The parameter is unused, let's remove it. Link: https://lkml.kernel.org/r/20210712124052.26491-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Acked-by: Heiko Carstens <hca@linux.ibm.com> [s390] Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Baoquan He <bhe@redhat.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Sergei Trofimovich <slyfox@gentoo.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Michel Lespinasse <michel@lespinasse.org> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com> Cc: Joe Perches <joe@perches.com> Cc: Pierre Morel <pmorel@linux.ibm.com> Cc: Jia He <justin.he@arm.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Len Brown <lenb@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Scott Cheloha <cheloha@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-07Merge tag 'pci-v5.15-changes' of ↵Linus Torvalds2-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration: - Convert controller drivers to generic_handle_domain_irq() (Marc Zyngier) - Simplify VPD (Vital Product Data) access and search (Heiner Kallweit) - Update bnx2, bnx2x, bnxt, cxgb4, cxlflash, sfc, tg3 drivers to use simplified VPD interfaces (Heiner Kallweit) - Run Max Payload Size quirks before configuring MPS; work around ASMedia ASM1062 SATA MPS issue (Marek Behún) Resource management: - Refactor pci_ioremap_bar() and pci_ioremap_wc_bar() (Krzysztof Wilczyński) - Optimize pci_resource_len() to reduce kernel size (Zhen Lei) PCI device hotplug: - Fix a double unmap in ibmphp (Vishal Aslot) PCIe port driver: - Enable Bandwidth Notification only if port supports it (Stuart Hayes) Sysfs/proc/syscalls: - Add schedule point in proc_bus_pci_read() (Krzysztof Wilczyński) - Return ~0 data on pciconfig_read() CAP_SYS_ADMIN failure (Krzysztof Wilczyński) - Return "int" from pciconfig_read() syscall (Krzysztof Wilczyński) Virtualization: - Extend "pci=noats" to also turn on Translation Blocking to protect against some DMA attacks (Alex Williamson) - Add sysfs mechanism to control the type of reset used between device assignments to VMs (Amey Narkhede) - Add support for ACPI _RST reset method (Shanker Donthineni) - Add ACS quirks for Cavium multi-function devices (George Cherian) - Add ACS quirks for NXP LX2xx0 and LX2xx2 platforms (Wasim Khan) - Allow HiSilicon AMBA devices that appear as fake PCI devices to use PASID and SVA (Zhangfei Gao) Endpoint framework: - Add support for SR-IOV Endpoint devices (Kishon Vijay Abraham I) - Zero-initialize endpoint test tool parameters so we don't use random parameters (Shunyong Yang) APM X-Gene PCIe controller driver: - Remove redundant dev_err() call in xgene_msi_probe() (ErKun Yang) Broadcom iProc PCIe controller driver: - Don't fail devm_pci_alloc_host_bridge() on missing 'ranges' because it's optional on BCMA devices (Rob Herring) - Fix BCMA probe resource handling (Rob Herring) Cadence PCIe driver: - Work around J7200 Link training electrical issue by increasing delays in LTSSM (Nadeem Athani) Intel IXP4xx PCI controller driver: - Depend on ARCH_IXP4XX to avoid useless config questions (Geert Uytterhoeven) Intel Keembay PCIe controller driver: - Add Intel Keem Bay PCIe controller (Srikanth Thokala) Marvell Aardvark PCIe controller driver: - Work around config space completion handling issues (Evan Wang) - Increase timeout for config access completions (Pali Rohár) - Emulate CRS Software Visibility bit (Pali Rohár) - Configure resources from DT 'ranges' property to fix I/O space access (Pali Rohár) - Serialize INTx mask/unmask (Pali Rohár) MediaTek PCIe controller driver: - Add MT7629 support in DT (Chuanjia Liu) - Fix an MSI issue (Chuanjia Liu) - Get syscon regmap ("mediatek,generic-pciecfg"), IRQ number ("pci_irq"), PCI domain ("linux,pci-domain") from DT properties if present (Chuanjia Liu) Microsoft Hyper-V host bridge driver: - Add ARM64 support (Boqun Feng) - Support "Create Interrupt v3" message (Sunil Muthuswamy) NVIDIA Tegra PCIe controller driver: - Use seq_puts(), move err_msg from stack to static, fix OF node leak (Christophe JAILLET) NVIDIA Tegra194 PCIe driver: - Disable suspend when in Endpoint mode (Om Prakash Singh) - Fix MSI-X address programming error (Om Prakash Singh) - Disable interrupts during suspend to avoid spurious AER link down (Om Prakash Singh) Renesas R-Car PCIe controller driver: - Work around hardware issue that prevents Link L1->L0 transition (Marek Vasut) - Fix runtime PM refcount leak (Dinghao Liu) Rockchip DesignWare PCIe controller driver: - Add Rockchip RK356X host controller driver (Simon Xue) TI J721E PCIe driver: - Add support for J7200 and AM64 (Kishon Vijay Abraham I) Toshiba Visconti PCIe controller driver: - Add Toshiba Visconti PCIe host controller driver (Nobuhiro Iwamatsu) Xilinx NWL PCIe controller driver: - Enable PCIe reference clock via CCF (Hyun Kwon) Miscellaneous: - Convert sta2x11 from 'pci_' to 'dma_' API (Christophe JAILLET) - Fix pci_dev_str_match_path() alloc while atomic bug (used for kernel parameters that specify devices) (Dan Carpenter) - Remove pointless Precision Time Management warning when PTM is present but not enabled (Jakub Kicinski) - Remove surplus "break" statements (Krzysztof Wilczyński)" * tag 'pci-v5.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (132 commits) PCI: ibmphp: Fix double unmap of io_mem x86/PCI: sta2x11: switch from 'pci_' to 'dma_' API PCI/VPD: Use unaligned access helpers PCI/VPD: Clean up public VPD defines and inline functions cxgb4: Use pci_vpd_find_id_string() to find VPD ID string PCI/VPD: Add pci_vpd_find_id_string() PCI/VPD: Include post-processing in pci_vpd_find_tag() PCI/VPD: Stop exporting pci_vpd_find_info_keyword() PCI/VPD: Stop exporting pci_vpd_find_tag() PCI: Set dma-can-stall for HiSilicon chips PCI: rockchip-dwc: Add Rockchip RK356X host controller driver PCI: dwc: Remove surplus break statement after return PCI: artpec6: Remove local code block from switch statement PCI: artpec6: Remove surplus break statement after return MAINTAINERS: Add entries for Toshiba Visconti PCIe controller PCI: visconti: Add Toshiba Visconti PCIe host controller driver PCI/portdrv: Enable Bandwidth Notification only if port supports it PCI: Allow PASID on fake PCIe devices without TLP prefixes PCI: mediatek: Use PCI domain to handle ports detection PCI: mediatek: Add new method to get irq number ...
2021-09-07Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds40-766/+1102
Pull KVM updates from Paolo Bonzini: "ARM: - Page ownership tracking between host EL1 and EL2 - Rely on userspace page tables to create large stage-2 mappings - Fix incompatibility between pKVM and kmemleak - Fix the PMU reset state, and improve the performance of the virtual PMU - Move over to the generic KVM entry code - Address PSCI reset issues w.r.t. save/restore - Preliminary rework for the upcoming pKVM fixed feature - A bunch of MM cleanups - a vGIC fix for timer spurious interrupts - Various cleanups s390: - enable interpretation of specification exceptions - fix a vcpu_idx vs vcpu_id mixup x86: - fast (lockless) page fault support for the new MMU - new MMU now the default - increased maximum allowed VCPU count - allow inhibit IRQs on KVM_RUN while debugging guests - let Hyper-V-enabled guests run with virtualized LAPIC as long as they do not enable the Hyper-V "AutoEOI" feature - fixes and optimizations for the toggling of AMD AVIC (virtualized LAPIC) - tuning for the case when two-dimensional paging (EPT/NPT) is disabled - bugfixes and cleanups, especially with respect to vCPU reset and choosing a paging mode based on CR0/CR4/EFER - support for 5-level page table on AMD processors Generic: - MMU notifier invalidation callbacks do not take mmu_lock unless necessary - improved caching of LRU kvm_memory_slot - support for histogram statistics - add statistics for halt polling and remote TLB flush requests" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (210 commits) KVM: Drop unused kvm_dirty_gfn_invalid() KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is adjusted KVM: MMU: mark role_regs and role accessors as maybe unused KVM: MIPS: Remove a "set but not used" variable x86/kvm: Don't enable IRQ when IRQ enabled in kvm_wait KVM: stats: Add VM stat for remote tlb flush requests KVM: Remove unnecessary export of kvm_{inc,dec}_notifier_count() KVM: x86/mmu: Move lpage_disallowed_link further "down" in kvm_mmu_page KVM: x86/mmu: Relocate kvm_mmu_page.tdp_mmu_page for better cache locality Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()" KVM: x86/mmu: Remove unused field mmio_cached in struct kvm_mmu_page kvm: x86: Increase KVM_SOFT_MAX_VCPUS to 710 kvm: x86: Increase MAX_VCPUS to 1024 kvm: x86: Set KVM_MAX_VCPU_ID to 4*KVM_MAX_VCPUS KVM: VMX: avoid running vmx_handle_exit_irqoff in case of emulation KVM: x86/mmu: Don't freak out if pml5_root is NULL on 4-level host KVM: s390: index kvm->arch.idle_mask by vcpu_idx KVM: s390: Enable specification exception interpretation KVM: arm64: Trim guest debug exception handling KVM: SVM: Add 5-level page table support for SVM ...
2021-09-06KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is ↵Zelin Deng1-0/+4
adjusted When MSR_IA32_TSC_ADJUST is written by guest due to TSC ADJUST feature especially there's a big tsc warp (like a new vCPU is hot-added into VM which has been up for a long time), tsc_offset is added by a large value then go back to guest. This causes system time jump as tsc_timestamp is not adjusted in the meantime and pvclock monotonic character. To fix this, just notify kvm to update vCPU's guest time before back to guest. Cc: stable@vger.kernel.org Signed-off-by: Zelin Deng <zelin.deng@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1619576521-81399-2-git-send-email-zelin.deng@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06KVM: MMU: mark role_regs and role accessors as maybe unusedPaolo Bonzini1-2/+2
It is reasonable for these functions to be used only in some configurations, for example only if the host is 64-bits (and therefore supports 64-bit guests). It is also reasonable to keep the role_regs and role accessors in sync even though some of the accessors may be used only for one of the two sets (as is the case currently for CR4.LA57).. Because clang reports warnings for unused inlines declared in a .c file, mark both sets of accessors as __maybe_unused. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06Merge tag 'kvmarm-5.15' of ↵Paolo Bonzini6-24/+33
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.15 - Page ownership tracking between host EL1 and EL2 - Rely on userspace page tables to create large stage-2 mappings - Fix incompatibility between pKVM and kmemleak - Fix the PMU reset state, and improve the performance of the virtual PMU - Move over to the generic KVM entry code - Address PSCI reset issues w.r.t. save/restore - Preliminary rework for the upcoming pKVM fixed feature - A bunch of MM cleanups - a vGIC fix for timer spurious interrupts - Various cleanups
2021-09-06x86/kvm: Don't enable IRQ when IRQ enabled in kvm_waitLai Jiangshan1-2/+3
Commit f4e61f0c9add3 ("x86/kvm: Fix broken irq restoration in kvm_wait") replaced "local_irq_restore() when IRQ enabled" with "local_irq_enable() when IRQ enabled" to suppress a warnning. Although there is no similar debugging warnning for doing local_irq_enable() when IRQ enabled as doing local_irq_restore() in the same IRQ situation. But doing local_irq_enable() when IRQ enabled is no less broken as doing local_irq_restore() and we'd better avoid it. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Message-Id: <20210814035129.154242-1-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06KVM: x86/mmu: Move lpage_disallowed_link further "down" in kvm_mmu_pageSean Christopherson1-1/+5
Move "lpage_disallowed_link" out of the first 64 bytes, i.e. out of the first cache line, of kvm_mmu_page so that "spt" and to a lesser extent "gfns" land in the first cache line. "lpage_disallowed_link" is accessed relatively infrequently compared to "spt", which is accessed any time KVM is walking and/or manipulating the shadow page tables. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210901221023.1303578-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06KVM: x86/mmu: Relocate kvm_mmu_page.tdp_mmu_page for better cache localitySean Christopherson1-2/+1
Move "tdp_mmu_page" into the 1-byte void left by the recently removed "mmio_cached" so that it resides in the first 64 bytes of kvm_mmu_page, i.e. in the same cache line as the most commonly accessed fields. Don't bother wrapping tdp_mmu_page in CONFIG_X86_64, including the field in 32-bit builds doesn't affect the size of kvm_mmu_page, and a future patch can always wrap the field in the unlikely event KVM gains a 1-byte flag that is 32-bit specific. Note, the size of kvm_mmu_page is also unchanged on CONFIG_X86_64=y due to it previously sharing an 8-byte chunk with write_flooding_count. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210901221023.1303578-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()"Sean Christopherson1-6/+0
Revert a misguided illegal GPA check when "translating" a non-nested GPA. The check is woefully incomplete as it does not fill in @exception as expected by all callers, which leads to KVM attempting to inject a bogus exception, potentially exposing kernel stack information in the process. WARNING: CPU: 0 PID: 8469 at arch/x86/kvm/x86.c:525 exception_type+0x98/0xb0 arch/x86/kvm/x86.c:525 CPU: 1 PID: 8469 Comm: syz-executor531 Not tainted 5.14.0-rc7-syzkaller #0 RIP: 0010:exception_type+0x98/0xb0 arch/x86/kvm/x86.c:525 Call Trace: x86_emulate_instruction+0xef6/0x1460 arch/x86/kvm/x86.c:7853 kvm_mmu_page_fault+0x2f0/0x1810 arch/x86/kvm/mmu/mmu.c:5199 handle_ept_misconfig+0xdf/0x3e0 arch/x86/kvm/vmx/vmx.c:5336 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6021 [inline] vmx_handle_exit+0x336/0x1800 arch/x86/kvm/vmx/vmx.c:6038 vcpu_enter_guest+0x2a1c/0x4430 arch/x86/kvm/x86.c:9712 vcpu_run arch/x86/kvm/x86.c:9779 [inline] kvm_arch_vcpu_ioctl_run+0x47d/0x1b20 arch/x86/kvm/x86.c:10010 kvm_vcpu_ioctl+0x49e/0xe50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3652 The bug has escaped notice because practically speaking the GPA check is useless. The GPA check in question only comes into play when KVM is walking guest page tables (or "translating" CR3), and KVM already handles illegal GPA checks by setting reserved bits in rsvd_bits_mask for each PxE, or in the case of CR3 for loading PTDPTRs, manually checks for an illegal CR3. This particular failure doesn't hit the existing reserved bits checks because syzbot sets guest.MAXPHYADDR=1, and IA32 architecture simply doesn't allow for such an absurd MAXPHYADDR, e.g. 32-bit paging doesn't define any reserved PA bits checks, which KVM emulates by only incorporating the reserved PA bits into the "high" bits, i.e. bits 63:32. Simply remove the bogus check. There is zero meaningful value and no architectural justification for supporting guest.MAXPHYADDR < 32, and properly filling the exception would introduce non-trivial complexity. This reverts commit ec7771ab471ba6a945350353617e2e3385d0e013. Fixes: ec7771ab471b ("KVM: x86: mmu: Add guest physical address check in translate_gpa()") Cc: stable@vger.kernel.org Reported-by: syzbot+200c08e88ae818f849ce@syzkaller.appspotmail.com Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210831164224.1119728-2-seanjc@google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06KVM: x86/mmu: Remove unused field mmio_cached in struct kvm_mmu_pageJia He1-1/+0
After reverting and restoring the fast tlb invalidation patch series, the mmio_cached is not removed. Hence a unused field is left in kvm_mmu_page. Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Jia He <justin.he@arm.com> Message-Id: <20210830145336.27183-1-justin.he@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06kvm: x86: Increase KVM_SOFT_MAX_VCPUS to 710Eduardo Habkost1-1/+1
Support for 710 VCPUs was tested by Red Hat since RHEL-8.4, so increase KVM_SOFT_MAX_VCPUS to 710. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Message-Id: <20210903211600.2002377-4-ehabkost@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06kvm: x86: Increase MAX_VCPUS to 1024Eduardo Habkost1-1/+1
Increase KVM_MAX_VCPUS to 1024, so we can test larger VMs. I'm not changing KVM_SOFT_MAX_VCPUS yet because I'm afraid it might involve complicated questions around the meaning of "supported" and "recommended" in the upstream tree. KVM_SOFT_MAX_VCPUS will be changed in a separate patch. For reference, visible effects of this change are: - KVM_CAP_MAX_VCPUS will now return 1024 (of course) - Default value for CPUID[HYPERV_CPUID_IMPLEMENT_LIMITS (00x40000005)].EAX will now be 1024 - KVM_MAX_VCPU_ID will change from 1151 to 4096 - Size of struct kvm will increase from 19328 to 22272 bytes (in x86_64) - Size of struct kvm_ioapic will increase from 1780 to 5084 bytes (in x86_64) - Bitmap stack variables that will grow: - At kvm_hv_flush_tlb() kvm_hv_send_ipi(), vp_bitmap[] and vcpu_bitmap[] will now be 128 bytes long - vcpu_bitmap at bioapic_write_indirect() will be 128 bytes long once patch "KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()" is applied Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Message-Id: <20210903211600.2002377-3-ehabkost@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06kvm: x86: Set KVM_MAX_VCPU_ID to 4*KVM_MAX_VCPUSEduardo Habkost1-1/+13
Instead of requiring KVM_MAX_VCPU_ID to be manually increased every time we increase KVM_MAX_VCPUS, set it to 4*KVM_MAX_VCPUS. This should be enough for CPU topologies where Cores-per-Package and Packages-per-Socket are not powers of 2. In practice, this increases KVM_MAX_VCPU_ID from 1023 to 1152. The only side effect of this change is making some fields in struct kvm_ioapic larger, increasing the struct size from 1628 to 1780 bytes (in x86_64). Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Message-Id: <20210903211600.2002377-2-ehabkost@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06KVM: VMX: avoid running vmx_handle_exit_irqoff in case of emulationMaxim Levitsky1-0/+3
If we are emulating an invalid guest state, we don't have a correct exit reason, and thus we shouldn't do anything in this function. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20210826095750.1650467-2-mlevitsk@redhat.com> Cc: stable@vger.kernel.org Fixes: 95b5a48c4f2b ("KVM: VMX: Handle NMIs, #MCs and async #PFs in common irqs-disabled fn", 2019-06-18) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-06KVM: x86/mmu: Don't freak out if pml5_root is NULL on 4-level hostSean Christopherson1-3/+11
Include pml5_root in the set of special roots if and only if the host, and thus NPT, is using 5-level paging. mmu_alloc_special_roots() expects special roots to be allocated as a bundle, i.e. they're either all valid or all NULL. But for pml5_root, that expectation only holds true if the host uses 5-level paging, which causes KVM to WARN about pml5_root being NULL when the other special roots are valid. The silver lining of 4-level vs. 5-level NPT being tied to the host kernel's paging level is that KVM's shadow root level is constant; unlike VMX's EPT, KVM can't choose 4-level NPT based on guest.MAXPHYADDR. That means KVM can still expect pml5_root to be bundled with the other special roots, it just needs to be conditioned on the shadow root level. Fixes: cb0f722aff6e ("KVM: x86/mmu: Support shadowing NPT when 5-level paging is enabled in host") Reported-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210824005824.205536-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-05Merge tag 'trace-v5.15' of ↵Linus Torvalds2-3/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - simplify the Kconfig use of FTRACE and TRACE_IRQFLAGS_SUPPORT - bootconfig can now start histograms - bootconfig supports group/all enabling - histograms now can put values in linear size buckets - execnames can be passed to synthetic events - introduce "event probes" that attach to other events and can retrieve data from pointers of fields, or record fields as different types (a pointer to a string as a string instead of just a hex number) - various fixes and clean ups * tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (35 commits) tracing/doc: Fix table format in histogram code selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes selftests/ftrace: Add selftest for testing eprobe events on synthetic events selftests/ftrace: Add test case to test adding and removing of event probe selftests/ftrace: Fix requirement check of README file selftests/ftrace: Add clear_dynamic_events() to test cases tracing: Add a probe that attaches to trace events tracing/probes: Reject events which have the same name of existing one tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs tracing/probe: Change traceprobe_set_print_fmt() to take a type tracing/probes: Use struct_size() instead of defining custom macros tracing/probes: Allow for dot delimiter as well as slash for system names tracing/probe: Have traceprobe_parse_probe_arg() take a const arg tracing: Have dynamic events have a ref counter tracing: Add DYNAMIC flag for dynamic events tracing: Replace deprecated CPU-hotplug functions. MAINTAINERS: Add an entry for os noise/latency tracepoint: Fix kerneldoc comments bootconfig/tracing/ktest: Update ktest example for boot-time tracing tools/bootconfig: Use per-group/all enable option in ftrace2bconf script ...
2021-09-04Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linuxLinus Torvalds1-5/+3
Pull MAP_DENYWRITE removal from David Hildenbrand: "Remove all in-tree usage of MAP_DENYWRITE from the kernel and remove VM_DENYWRITE. There are some (minor) user-visible changes: - We no longer deny write access to shared libaries loaded via legacy uselib(); this behavior matches modern user space e.g. dlopen(). - We no longer deny write access to the elf interpreter after exec completed, treating it just like shared libraries (which it often is). - We always deny write access to the file linked via /proc/pid/exe: sys_prctl(PR_SET_MM_MAP/EXE_FILE) will fail if write access to the file cannot be denied, and write access to the file will remain denied until the link is effectivel gone (exec, termination, sys_prctl(PR_SET_MM_MAP/EXE_FILE)) -- just as if exec'ing the file. Cross-compiled for a bunch of architectures (alpha, microblaze, i386, s390x, ...) and verified via ltp that especially the relevant tests (i.e., creat07 and execve04) continue working as expected" * tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux: fs: update documentation of get_write_access() and friends mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff() mm: remove VM_DENYWRITE binfmt: remove in-tree usage of MAP_DENYWRITE kernel/fork: always deny write access to current MM exe_file kernel/fork: factor out replacing the current MM exe_file binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()
2021-09-03Merge tag 'kbuild-v5.15' of ↵Linus Torvalds4-9/+3
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Add -s option (strict mode) to merge_config.sh to make it fail when any symbol is redefined. - Show a warning if a different compiler is used for building external modules. - Infer --target from ARCH for CC=clang to let you cross-compile the kernel without CROSS_COMPILE. - Make the integrated assembler default (LLVM_IAS=1) for CC=clang. - Add <linux/stdarg.h> to the kernel source instead of borrowing <stdarg.h> from the compiler. - Add Nick Desaulniers as a Kbuild reviewer. - Drop stale cc-option tests. - Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG to handle symbols in inline assembly. - Show a warning if 'FORCE' is missing for if_changed rules. - Various cleanups * tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits) kbuild: redo fake deps at include/ksym/*.h kbuild: clean up objtool_args slightly modpost: get the *.mod file path more simply checkkconfigsymbols.py: Fix the '--ignore' option kbuild: merge vmlinux_link() between ARCH=um and other architectures kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh kbuild: merge vmlinux_link() between the ordinary link and Clang LTO kbuild: remove stale *.symversions kbuild: remove unused quiet_cmd_update_lto_symversions gen_compile_commands: extract compiler command from a series of commands x86: remove cc-option-yn test for -mtune= arc: replace cc-option-yn uses with cc-option s390: replace cc-option-yn uses with cc-option ia64: move core-y in arch/ia64/Makefile to arch/ia64/Kbuild sparc: move the install rule to arch/sparc/Makefile security: remove unneeded subdir-$(CONFIG_...) kbuild: sh: remove unused install script kbuild: Fix 'no symbols' warning when CONFIG_TRIM_UNUSD_KSYMS=y kbuild: Switch to 'f' variants of integrated assembler flag kbuild: Shuffle blank line to improve comment meaning ...
2021-09-03Merge branch 'akpm' (patches from Andrew)Linus Torvalds8-21/+27
Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ...
2021-09-03mm: wire up syscall process_mreleaseSuren Baghdasaryan2-0/+2
Split off from prev patch in the series that implements the syscall. Link: https://lkml.kernel.org/r/20210809185259.405936-2-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Jan Engelhardt <jengelh@inai.de> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tim Murray <timmurray@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03memblock: make memblock_find_in_range method privateMike Rapoport5-18/+22
There are a lot of uses of memblock_find_in_range() along with memblock_reserve() from the times memblock allocation APIs did not exist. memblock_find_in_range() is the very core of memblock allocations, so any future changes to its internal behaviour would mandate updates of all the users outside memblock. Replace the calls to memblock_find_in_range() with an equivalent calls to memblock_phys_alloc() and memblock_phys_alloc_range() and make memblock_find_in_range() private method of memblock. This simplifies the callers, ensures that (unlikely) errors in memblock_reserve() are handled and improves maintainability of memblock_find_in_range(). Link: https://lkml.kernel.org/r/20210816122622.30279-1-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> [arm64] Acked-by: Kirill A. Shutemov <kirill.shtuemov@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [ACPI] Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Nick Kossifidis <mick@ics.forth.gr> [riscv] Tested-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03memcg: enable accounting for ldt_struct objectsVasily Averin1-3/+3
Each task can request own LDT and force the kernel to allocate up to 64Kb memory per-mm. There are legitimate workloads with hundreds of processes and there can be hundreds of workloads running on large machines. The unaccounted memory can cause isolation issues between the workloads particularly on highly utilized machines. It makes sense to account for this objects to restrict the host's memory consumption from inside the memcg-limited container. Link: https://lkml.kernel.org/r/38010594-50fe-c06d-7cb0-d1f77ca422f3@virtuozzo.com Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Acked-by: Borislav Petkov <bp@suse.de> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrei Vagin <avagin@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Roman Gushchin <guro@fb.com> Cc: Serge Hallyn <serge@hallyn.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Yutian Yang <nglaive@gmail.com> Cc: Zefan Li <lizefan.x@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03binfmt: remove in-tree usage of MAP_DENYWRITEDavid Hildenbrand1-4/+2
At exec time when we mmap the new executable via MAP_DENYWRITE we have it opened via do_open_execat() and already deny_write_access()'ed the file successfully. Once exec completes, we allow_write_acces(); however, we set mm->exe_file in begin_new_exec() via set_mm_exe_file() and also deny_write_access() as long as mm->exe_file remains set. We'll effectively deny write access to our executable via mm->exe_file until mm->exe_file is changed -- when the process is removed, on new exec, or via sys_prctl(PR_SET_MM_MAP/EXE_FILE). Let's remove all usage of MAP_DENYWRITE, it's no longer necessary for mm->exe_file. In case of an elf interpreter, we'll now only deny write access to the file during exec. This is somewhat okay, because the interpreter behaves (and sometime is) a shared library; all shared libraries, especially the ones loaded directly in user space like via dlopen() won't ever be mapped via MAP_DENYWRITE, because we ignore that from user space completely; these shared libraries can always be modified while mapped and executed. Let's only special-case the main executable, denying write access while being executed by a process. This can be considered a minor user space visible change. While this is a cleanup, it also fixes part of a problem reported with VM_DENYWRITE on overlayfs, as VM_DENYWRITE is effectively unused with this patch and will be removed next: "Overlayfs did not honor positive i_writecount on realfile for VM_DENYWRITE mappings." [1] [1] https://lore.kernel.org/r/YNHXzBgzRrZu1MrD@miu.piliscsaba.redhat.com/ Reported-by: Chengguang Xu <cgxu519@mykernel.net> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: David Hildenbrand <david@redhat.com>
2021-09-03binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()David Hildenbrand1-1/+1
uselib() is the legacy systemcall for loading shared libraries. Nowadays, applications use dlopen() to load shared libraries, completely implemented in user space via mmap(). For example, glibc uses MAP_COPY to mmap shared libraries. While this maps to MAP_PRIVATE | MAP_DENYWRITE on Linux, Linux ignores any MAP_DENYWRITE specification from user space in mmap. With this change, all remaining in-tree users of MAP_DENYWRITE use it to map an executable. We will be able to open shared libraries loaded via uselib() writable, just as we already can via dlopen() from user space. This is one step into the direction of removing MAP_DENYWRITE from the kernel. This can be considered a minor user space visible change. Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: David Hildenbrand <david@redhat.com>
2021-09-03x86: remove cc-option-yn test for -mtune=Nick Desaulniers1-6/+0
As noted in the comment, -mtune= has been supported since GCC 3.4. The minimum required version of GCC to build the kernel (as specified in Documentation/process/changes.rst) is GCC 4.9. tune is not immediately expanded. Instead it defines a macro that will test via cc-option later values for -mtune=. But we can skip the test whether to use -mtune= vs. -mcpu=. Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-09-03x86/build/vdso: fix missing FORCE for *.so build ruleMasahiro Yamada1-1/+1
Add FORCE so that if_changed can detect the command line change. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-09-02Merge tag 'for-linus-5.15-rc1-tag' of ↵Linus Torvalds5-22/+15
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - some small cleanups - a fix for a bug when running as Xen PV guest which could result in not all memory being transferred in case of a migration of the guest - a small series for getting rid of code for supporting very old Xen hypervisor versions nobody should be using since many years now - a series for hardening the Xen block frontend driver - a fix for Xen PV boot code issuing warning messages due to a stray preempt_disable() on the non-boot processors * tag 'for-linus-5.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: remove stray preempt_disable() from PV AP startup code xen/pcifront: Removed unnecessary __ref annotation x86: xen: platform-pci-unplug: use pr_err() and pr_warn() instead of raw printk() drivers/xen/xenbus/xenbus_client.c: fix bugon.cocci warnings xen/blkfront: don't trust the backend response data blindly xen/blkfront: don't take local copy of a request from the ring page xen/blkfront: read response from backend only once xen: assume XENFEAT_gnttab_map_avail_bits being set for pv guests xen: assume XENFEAT_mmu_pt_update_preserve_ad being set for pv guests xen: check required Xen features xen: fix setting of max_pfn in shared_info