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2024-08-22KVM: x86: Acquire kvm->srcu when handling KVM_SET_VCPU_EVENTSSean Christopherson1-0/+2
Grab kvm->srcu when processing KVM_SET_VCPU_EVENTS, as KVM will forcibly leave nested VMX/SVM if SMM mode is being toggled, and leaving nested VMX reads guest memory. Note, kvm_vcpu_ioctl_x86_set_vcpu_events() can also be called from KVM_RUN via sync_regs(), which already holds SRCU. I.e. trying to precisely use kvm_vcpu_srcu_read_lock() around the problematic SMM code would cause problems. Acquiring SRCU isn't all that expensive, so for simplicity, grab it unconditionally for KVM_SET_VCPU_EVENTS. ============================= WARNING: suspicious RCU usage 6.10.0-rc7-332d2c1d713e-next-vm #552 Not tainted ----------------------------- include/linux/kvm_host.h:1027 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by repro/1071: #0: ffff88811e424430 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x7d/0x970 [kvm] stack backtrace: CPU: 15 PID: 1071 Comm: repro Not tainted 6.10.0-rc7-332d2c1d713e-next-vm #552 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: <TASK> dump_stack_lvl+0x7f/0x90 lockdep_rcu_suspicious+0x13f/0x1a0 kvm_vcpu_gfn_to_memslot+0x168/0x190 [kvm] kvm_vcpu_read_guest+0x3e/0x90 [kvm] nested_vmx_load_msr+0x6b/0x1d0 [kvm_intel] load_vmcs12_host_state+0x432/0xb40 [kvm_intel] vmx_leave_nested+0x30/0x40 [kvm_intel] kvm_vcpu_ioctl_x86_set_vcpu_events+0x15d/0x2b0 [kvm] kvm_arch_vcpu_ioctl+0x1107/0x1750 [kvm] ? mark_held_locks+0x49/0x70 ? kvm_vcpu_ioctl+0x7d/0x970 [kvm] ? kvm_vcpu_ioctl+0x497/0x970 [kvm] kvm_vcpu_ioctl+0x497/0x970 [kvm] ? lock_acquire+0xba/0x2d0 ? find_held_lock+0x2b/0x80 ? do_user_addr_fault+0x40c/0x6f0 ? lock_release+0xb7/0x270 __x64_sys_ioctl+0x82/0xb0 do_syscall_64+0x6c/0x170 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7ff11eb1b539 </TASK> Fixes: f7e570780efc ("KVM: x86: Forcibly leave nested virt when SMM state is toggled") Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2024-08-22KVM: x86/mmu: Check that root is valid/loaded when pre-faulting SPTEsSean Christopherson1-1/+3
Error out if kvm_mmu_reload() fails when pre-faulting memory, as trying to fault-in SPTEs will fail miserably due to root.hpa pointing at garbage. Note, kvm_mmu_reload() can return -EIO and thus trigger the WARN on -EIO in kvm_vcpu_pre_fault_memory(), but all such paths also WARN, i.e. the WARN isn't user-triggerable and won't run afoul of warn-on-panic because the kernel would already be panicking. BUG: unable to handle page fault for address: 000029ffffffffe8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP CPU: 22 PID: 1069 Comm: pre_fault_memor Not tainted 6.10.0-rc7-332d2c1d713e-next-vm #548 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:is_page_fault_stale+0x3e/0xe0 [kvm] RSP: 0018:ffffc9000114bd48 EFLAGS: 00010206 RAX: 00003fffffffffc0 RBX: ffff88810a07c080 RCX: ffffc9000114bd78 RDX: ffff88810a07c080 RSI: ffffea0000000000 RDI: ffff88810a07c080 RBP: ffffc9000114bd78 R08: 00007fa3c8c00000 R09: 8000000000000225 R10: ffffea00043d7d80 R11: 0000000000000000 R12: ffff88810a07c080 R13: 0000000100000000 R14: ffffc9000114be58 R15: 0000000000000000 FS: 00007fa3c9da0740(0000) GS:ffff888277d80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000029ffffffffe8 CR3: 000000011d698000 CR4: 0000000000352eb0 Call Trace: <TASK> kvm_tdp_page_fault+0xcc/0x160 [kvm] kvm_mmu_do_page_fault+0xfb/0x1f0 [kvm] kvm_arch_vcpu_pre_fault_memory+0xd0/0x1a0 [kvm] kvm_vcpu_ioctl+0x761/0x8c0 [kvm] __x64_sys_ioctl+0x82/0xb0 do_syscall_64+0x5b/0x160 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK> Modules linked in: kvm_intel kvm CR2: 000029ffffffffe8 ---[ end trace 0000000000000000 ]--- Fixes: 6e01b7601dfe ("KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory()") Reported-by: [email protected] Closes: https://lore.kernel.org/all/[email protected] Reviewed-by: Kai Huang <[email protected]> Tested-by: xingwei lee <[email protected]> Tested-by: yuxin wang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2024-08-22KVM: x86/mmu: Fixup comments missed by the REMOVED_SPTE=>FROZEN_SPTE renameYan Zhao3-8/+8
Replace "removed" with "frozen" in comments as appropriate to complete the rename of REMOVED_SPTE to FROZEN_SPTE. Fixes: 964cea817196 ("KVM: x86/tdp_mmu: Rename REMOVED_SPTE to FROZEN_SPTE") Signed-off-by: Yan Zhao <[email protected]> Signed-off-by: Rick Edgecombe <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: write changelog] Signed-off-by: Sean Christopherson <[email protected]>
2024-08-22KVM: x86: Advertise AVX10.1 CPUID to userspaceTao Su3-2/+37
Advertise AVX10.1 related CPUIDs, i.e. report AVX10 support bit via CPUID.(EAX=07H, ECX=01H):EDX[bit 19] and new CPUID leaf 0x24H so that guest OS and applications can query the AVX10.1 CPUIDs directly. Intel AVX10 represents the first major new vector ISA since the introduction of Intel AVX512, which will establish a common, converged vector instruction set across all Intel architectures[1]. AVX10.1 is an early version of AVX10, that enumerates the Intel AVX512 instruction set at 128, 256, and 512 bits which is enabled on Granite Rapids. I.e., AVX10.1 is only a new CPUID enumeration with no new functionality. New features, e.g. Embedded Rounding and Suppress All Exceptions (SAE) will be introduced in AVX10.2. Advertising AVX10.1 is safe because there is nothing to enable for AVX10.1, i.e. it's purely a new way to enumerate support, thus there will never be anything for the kernel to enable. Note just the CPUID checking is changed when using AVX512 related instructions, e.g. if using one AVX512 instruction needs to check (AVX512 AND AVX512DQ), it can check ((AVX512 AND AVX512DQ) OR AVX10.1) after checking XCR0[7:5]. The versions of AVX10 are expected to be inclusive, e.g. version N+1 is a superset of version N. Per the spec, the version can never be 0, just advertise AVX10.1 if it's supported in hardware. Moreover, advertising AVX10_{128,256,512} needs to land in the same commit as advertising basic AVX10.1 support, otherwise KVM would advertise an impossible CPU model. E.g. a CPU with AVX512 but not AVX10.1/512 is impossible per the SDM. As more and more AVX related CPUIDs are added (it would have resulted in around 40-50 CPUID flags when developing AVX10), the versioning approach is introduced. But incrementing version numbers are bad for virtualization. E.g. if AVX10.2 has a feature that shouldn't be enumerated to guests for whatever reason, then KVM can't enumerate any "later" features either, because the only way to hide the problematic AVX10.2 feature is to set the version to AVX10.1 or lower[2]. But most AVX features are just passed through and don't have virtualization controls, so AVX10 should not be problematic in practice, so long as Intel honors their promise that future versions will be supersets of past versions. [1] https://cdrdv2.intel.com/v1/dl/getContent/784267 [2] https://lore.kernel.org/all/[email protected]/ Suggested-by: Sean Christopherson <[email protected]> Signed-off-by: Tao Su <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: minor changelog tweaks] Signed-off-by: Sean Christopherson <[email protected]>
2024-08-22KVM: x86: Optimize local variable in start_sw_tscdeadline()Thorsten Blum1-1/+1
Change the data type of the local variable this_tsc_khz to u32 because virtual_tsc_khz is also declared as u32. Since do_div() casts the divisor to u32 anyway, changing the data type of this_tsc_khz to u32 also removes the following Coccinelle/coccicheck warning reported by do_div.cocci: WARNING: do_div() does a 64-by-32 division, please consider using div64_ul instead Signed-off-by: Thorsten Blum <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2024-08-22drm/xe: Fix missing runtime outer protection for ggtt_remove_nodeRodrigo Vivi2-39/+73
Defer the ggtt node removal to a thread if runtime_pm is not active. The ggtt node removal can be called from multiple places, including places where we cannot protect with outer callers and places we are within other locks. So, try to grab the runtime reference if the device is already active, otherwise defer the removal to a separate thread from where we are sure we can wake the device up. v2: - use xe wq instead of system wq (Matt and CI) - Avoid GFP_KERNEL to be future proof since this removal can be called from outside our drivers and we don't want to block if atomic is needed. (Brost) v3: amend forgot chunk declaring xe_device. v4: Use a xe_ggtt_region to encapsulate the node and remova info, wihtout the need for any memory allocation at runtime. v5: Actually fill the delayed_removal.invalidate (Brost) v6: - Ensure that ggtt_region is not freed before work finishes (Auld) - Own wq to ensures that the queued works are flushed before ggtt_fini (Brost) v7: also free ggtt_region on early !bound return (Auld) v8: Address the null deref (CI) v9: Based on the new xe_ggtt_node for the proper care of the lifetime of the object. v10: Redo the lost v5 change. (Brost) v11: Simplify the invalidate_on_remove (Lucas) Cc: Matthew Auld <[email protected]> Cc: Paulo Zanoni <[email protected]> Cc: Francois Dugast <[email protected]> Cc: Thomas Hellström <[email protected]> Cc: Matthew Brost <[email protected]> Reviewed-by: Lucas De Marchi <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Make xe_ggtt_node struct independentRodrigo Vivi12-104/+214
In some rare cases, the drm_mm node cannot be removed synchronously due to runtime PM conditions. In this situation, the node removal will be delegated to a workqueue that will be able to wake up the device before removing the node. However, in this situation, the lifetime of the xe_ggtt_node cannot be restricted to the lifetime of the parent object. So, this patch introduces the infrastructure so the xe_ggtt_node struct can be allocated in advance and freed when needed. By having the ggtt backpointer, it also ensure that the init function is always called before any attempt to insert or reserve the node in the GGTT. v2: s/xe_ggtt_node_force_fini/xe_ggtt_node_fini and use it internaly (Brost) v3: - Use GF_NOFS for node allocation (CI) - Avoid ggtt argument, now that we have it inside the node (Lucas) - Fix some missed fini cases (CI) v4: - Fix SRIOV critical case where config->ggtt_region was lost (Michal) - Avoid ggtt argument also on removal (missed case on v3) (Michal) - Remove useless checks (Michal) - Return 0 instead of negative errno on a u32 addr. (Michal) - s/xe_ggtt_assign/xe_ggtt_node_assign for coherence, while we are touching it (Michal) v5: - Fix VFs' ggtt_balloon Cc: Matthew Auld <[email protected]> Cc: Michal Wajdeczko <[email protected]> Cc: Matthew Brost <[email protected]> Reviewed-by: Matthew Brost <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Refactor xe_ggtt balloon functions to make the node clearRodrigo Vivi3-15/+18
These operations are related to node. Convert them to the new appropriate name space xe_ggtt_node. v2: Also move arguments around for consistency (Lucas). v3: s/node_balloon/node_insert_balloon and s/node_deballoon/node_remove_balloon (Michal). Reviewed-by: Lucas De Marchi <[email protected]> Cc: Michal Wajdeczko <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Introduce xe_ggtt_print_holesRodrigo Vivi3-24/+42
Introduce a new xe_ggtt_print_holes helper that attends the SRIOV demand and finishes the goal of limiting drm_mm access to xe_ggtt. Cc: Michal Wajdeczko <[email protected]> Reviewed-by: Jonathan Cavitt <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Introduce xe_ggtt_largest_holeRodrigo Vivi3-21/+38
Introduce a new xe_ggtt_largest_hole helper that attends the SRIOV demand and continue with the goal of limiting drm_mm access to xe_ggtt. v2: Fix a typo (Michal) Cc: Michal Wajdeczko <[email protected]> Reviewed-by: Lucas De Marchi <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Limit drm_mm_node_allocated access to xe_ggtt_nodeRodrigo Vivi4-7/+19
Continue with the encapsulation of drm_mm_node inside xe_ggtt. Cc: Michal Wajdeczko <[email protected]> Reviewed-by: Matthew Brost <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Rename xe_ggtt_node related functionsRodrigo Vivi4-56/+54
Bring some consistency and prepare for more xe_ggtt_node related functions to be introduced. Reviewed-by: Matthew Brost <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Encapsulate drm_mm_node inside xe_ggtt_nodeRodrigo Vivi11-78/+90
The xe_ggtt component uses drm_mm to manage the GGTT. The drm_mm_node is just a node inside drm_mm, but in Xe we use that only in the GGTT context. So, this patch encapsulates the drm_mm_node into a xe_ggtt's new struct. This is the first step towards limiting all the drm_mm access through xe_ggtt. The ultimate goal is to have a better control of the node insertion and removal, so the removal can be delegated to a delayed workqueue. v2: Fix includes and typos (Michal and Brost) Reviewed-by: Matthew Brost <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/{i915, xe}: Avoid direct inspection of dpt_vma from outside dptRodrigo Vivi4-3/+16
DPT code is so dependent on i915 vma implementation and it is not ported yet to Xe. This patch limits inspection to DPT's VMA struct to intel_dpt component only, so the Xe GGTT code can evolve. Cc: Matthew Brost <[email protected]> Cc: Maarten Lankhorst <[email protected]> Cc: Juha-Pekka Heikkila <[email protected]> Reviewed-by: Jonathan Cavitt <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Remove unnecessary drm_mm.h includesRodrigo Vivi3-3/+1
These includes are no longer necessary, and where appropriate are replaced by the linux/types.h one. Reviewed-by: Jonathan Cavitt <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Introduce GGTT documentationRodrigo Vivi3-35/+150
Document xe_ggtt and ensure it is part of the built kernel docs. v2: - Accepted all Michal's suggestions - Rebased on top of new set_pte per platform/wa function pointer v3: - Typos and other acronym fixes (Michal) Cc: Matthew Brost <[email protected]> Cc: Michal Wajdeczko <[email protected]> Reviewed-by: Himal Prasad Ghimiray <[email protected]> #v1 Reviewed-by: Lucas De Marchi <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-22drm/xe: Removed unused xe_ggtt_printkRodrigo Vivi2-21/+0
Apparently this was only useful when enabling ggtt support for the very first time and never used again. It is also not useful now that we have the ggtt_dump available through debugfs. Reviewed-by: Himal Prasad Ghimiray <[email protected]> Reviewed-by: Lucas De Marchi <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Rodrigo Vivi <[email protected]>
2024-08-23kbuild: fix typos "prequisites" to "prerequisites"Masahiro Yamada4-4/+4
This typo in scripts/Makefile.build has been present for more than 20 years. It was accidentally copy-pasted to other scripts/Makefile.* files. Fix them all. Signed-off-by: Masahiro Yamada <[email protected]> Reviewed-by: Nathan Chancellor <[email protected]>
2024-08-22smb: client: ignore unhandled reparse tagsPaulo Alcantara1-4/+7
Just ignore reparse points that the client can't parse rather than bailing out and not opening the file or directory. Reported-by: Marc <[email protected]> Closes: https://lore.kernel.org/r/CAMHwNVv-B+Q6wa0FEXrAuzdchzcJRsPKDDRrNaYZJd6X-+iJzw@mail.gmail.com Fixes: 539aad7f14da ("smb: client: introduce ->parse_reparse_point()") Tested-by: Anthony Nandaa (Microsoft) <[email protected]> Signed-off-by: Paulo Alcantara (Red Hat) <[email protected]> Signed-off-by: Steve French <[email protected]>
2024-08-22smb3: fix problem unloading module due to leaked refcount on shutdownSteve French3-0/+6
The shutdown ioctl can leak a refcount on the tlink which can prevent rmmod (unloading the cifs.ko) module from working. Found while debugging xfstest generic/043 Fixes: 69ca1f57555f ("smb3: add dynamic tracepoints for shutdown ioctl") Reviewed-by: Meetakshi Setiya <[email protected]> Reviewed-by: Shyam Prasad N <[email protected]> Signed-off-by: Steve French <[email protected]>
2024-08-22s390/early: Dump register contents and call trace for early crashesHeiko Carstens3-4/+24
If the early program check handler cannot resolve a program check dump register contents and a call trace to the console before loading a disabled wait psw. This makes debugging much easier. Emit an extra message with early_printk() for cases where regular printk() via the early console is not yet working so that at least some information is available. Signed-off-by: Heiko Carstens <[email protected]> Acked-by: Vasily Gorbik <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2024-08-22s390/early: Add __init to __do_early_pgm_check()Heiko Carstens1-1/+1
__do_early_pgm_check() is a function which is only needed during early setup code. Mark it __init in order to save a few bytes. Signed-off-by: Heiko Carstens <[email protected]> Acked-by: Alexander Gordeev <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2024-08-22s390/cpum_sf: Remove WARN_ON_ONCE statementsThomas Richter1-8/+4
Remove WARN_ON_ONCE statements. These have not triggered in the past. Signed-off-by: Thomas Richter <[email protected]> Acked-by: Sumanth Korikkar <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Alexander Gordeev <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2024-08-22s390/cpum_sf: Rework debug_sprintf_event() messagesThomas Richter1-137/+10
Rework debug messages: - Remove most of the debug_sprintf_event() invocations. - Do not split string format statements - Remove colon after function name. Signed-off-by: Thomas Richter <[email protected]> Acked-by: Sumanth Korikkar <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Alexander Gordeev <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2024-08-22s390/boot: Fix KASLR base offset off by __START_KERNEL bytesAlexander Gordeev6-31/+52
Symbol offsets to the KASLR base do not match symbol address in the vmlinux image. That is the result of setting the KASLR base to the beginning of .text section as result of an optimization. Revert that optimization and allocate virtual memory for the whole kernel image including __START_KERNEL bytes as per the linker script. That allows keeping the semantics of the KASLR base offset in sync with other architectures. Rename __START_KERNEL to TEXT_OFFSET, since it represents the offset of the .text section within the kernel image, rather than a virtual address. Still skip mapping TEXT_OFFSET bytes to save memory on pgtables and provoke exceptions in case an attempt to access this area is made, as no kernel symbol may reside there. In case CONFIG_KASAN is enabled the location counter might exceed the value of TEXT_OFFSET, while the decompressor linker script forcefully resets it to TEXT_OFFSET, which leads to a sections overlap link failure. Use MAX() expression to avoid that. Reported-by: Omar Sandoval <[email protected]> Closes: https://lore.kernel.org/linux-s390/[email protected]/ Fixes: 56b1069c40c7 ("s390/boot: Rework deployment of the kernel image") Signed-off-by: Alexander Gordeev <[email protected]> Acked-by: Vasily Gorbik <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2024-08-22s390/boot: Avoid possible physmem_info segment corruptionAlexander Gordeev1-2/+2
When physical memory for the kernel image is allocated it does not consider extra memory required for offsetting the image start to match it with the lower 20 bits of KASLR virtual base address. That might lead to kernel access beyond its memory range. Suggested-by: Vasily Gorbik <[email protected]> Fixes: 693d41f7c938 ("s390/mm: Restore mapping of kernel image using large pages") Signed-off-by: Alexander Gordeev <[email protected]> Acked-by: Vasily Gorbik <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2024-08-22perf python: Allow checking for the existence of warning options in clangArnaldo Carvalho de Melo1-1/+1
We'll need to check if an warning option introduced in clang 19 is available on the clang version being used, so cover the error message emitted when testing for a -W option. Tested-by: Sedat Dilek <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Nathan Chancellor <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: https://lore.kernel.org/lkml/CA+icZUVtHn8X1Tb_Y__c-WswsO0K8U9uy3r2MzKXwTA5THtL7w@mail.gmail.com Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2024-08-22KVM: arm64: Make the exposed feature bits in AA64DFR0_EL1 writable from ↵Shameer Kolothum2-1/+17
userspace KVM exposes the OS double lock feature bit to Guests but returns RAZ/WI on Guest OSDLR_EL1 access. This breaks Guest migration between systems where this feature differ. Add support to make this feature writable from userspace by setting the mask bit. While at it, set the mask bits for the exposed WRPs(Number of Watchpoints) as well. Also update the selftest to cover these fields. However we still can't make BRPs and CTX_CMPs fields writable, because as per ARM ARM DDI 0487K.a, section D2.8.3 Breakpoint types and linking of breakpoints, highest numbered breakpoints(BRPs) must be context aware breakpoints(CTX_CMPs). KVM does not trap + emulate the breakpoint registers, and as such cannot support a layout that misaligns with the underlying hardware. Reviewed-by: Oliver Upton <[email protected]> Signed-off-by: Shameer Kolothum <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Marc Zyngier <[email protected]>
2024-08-22nvme_core: scan namespaces asynchronouslyStuart Hayes1-1/+39
Use async function calls to make namespace scanning happen in parallel. Without the patch, NVME namespaces are scanned serially, so it can take a long time for all of a controller's namespaces to become available, especially with a slower (TCP) interface with large number of namespaces. It is not uncommon to have large numbers (hundreds or thousands) of namespaces on nvme-of with storage servers. The time it took for all namespaces to show up after connecting (via TCP) to a controller with 1002 namespaces was measured on one system: network latency without patch with patch 0 6s 1s 50ms 210s 10s 100ms 417s 18s Measurements taken on another system show the effect of the patch on the time nvme_scan_work() took to complete, when connecting to a linux nvme-of target with varying numbers of namespaces, on a network of 400us. namespaces without patch with patch 1 16ms 14ms 2 24ms 16ms 4 49ms 22ms 8 101ms 33ms 16 207ms 56ms 100 1.4s 0.6s 1000 12.9s 2.0s On the same system, connecting to a local PCIe NVMe drive (a Samsung PM1733) instead of a network target: namespaces without patch with patch 1 13ms 12ms 2 41ms 13ms Signed-off-by: Stuart Hayes <[email protected]> Reviewed-by: Sagi Grimberg <[email protected]>
2024-08-22regulator: s2mps11: use scoped memory allocation to simplify probeKrzysztof Kozlowski1-10/+7
Allocate the memory with scoped/cleanup.h to reduce error handling (less error paths) and make the code a bit simpler. Signed-off-by: Krzysztof Kozlowski <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Mark Brown <[email protected]>
2024-08-22ASoC: cs-amp-lib: Ignore empty UEFI calibration entriesRichard Fitzgerald1-1/+6
If the timestamp of a calibration entry is 0 it is an unused entry and must be ignored. Some end-products reserve EFI space for calibration entries by shipping with a zero-filled EFI file. When searching the file for calibration data the driver must skip the empty entries. The timestamp of a valid entry is always non-zero. Signed-off-by: Richard Fitzgerald <[email protected]> Fixes: 1cad8725f2b9 ("ASoC: cs-amp-lib: Add helpers for factory calibration data") Link: https://patch.msgid.link/[email protected] Signed-off-by: Mark Brown <[email protected]>
2024-08-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfAlexei Starovoitov1334-9273/+19542
Cross-merge bpf fixes after downstream PR including important fixes (from bpf-next point of view): commit 41c24102af7b ("selftests/bpf: Filter out _GNU_SOURCE when compiling test_cpp") commit fdad456cbcca ("bpf: Fix updating attached freplace prog in prog_array map") No conflicts. Adjacent changes in: include/linux/bpf_verifier.h kernel/bpf/verifier.c tools/testing/selftests/bpf/Makefile Link: https://lore.kernel.org/bpf/[email protected]/ Signed-off-by: Alexei Starovoitov <[email protected]>
2024-08-22dm bufio: Remove NULL check of list_entry()Yuesong Li1-3/+0
list_entry() will never return a NULL pointer, thus remove the check. Signed-off-by: Yuesong Li <[email protected]> Signed-off-by: Mikulas Patocka <[email protected]>
2024-08-22ipe: Remove duplicated include in ipe.cYang Li1-1/+0
The header files eval.h is included twice in ipe.c, so one inclusion of each can be removed. Reported-by: Abaci Robot <[email protected]> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9796 Signed-off-by: Yang Li <[email protected]> Signed-off-by: Paul Moore <[email protected]>
2024-08-22lsm: replace indirect LSM hook calls with static callsKP Singh2-73/+198
LSM hooks are currently invoked from a linked list as indirect calls which are invoked using retpolines as a mitigation for speculative attacks (Branch History / Target injection) and add extra overhead which is especially bad in kernel hot paths: security_file_ioctl: 0xff...0320 <+0>: endbr64 0xff...0324 <+4>: push %rbp 0xff...0325 <+5>: push %r15 0xff...0327 <+7>: push %r14 0xff...0329 <+9>: push %rbx 0xff...032a <+10>: mov %rdx,%rbx 0xff...032d <+13>: mov %esi,%ebp 0xff...032f <+15>: mov %rdi,%r14 0xff...0332 <+18>: mov $0xff...7030,%r15 0xff...0339 <+25>: mov (%r15),%r15 0xff...033c <+28>: test %r15,%r15 0xff...033f <+31>: je 0xff...0358 <security_file_ioctl+56> 0xff...0341 <+33>: mov 0x18(%r15),%r11 0xff...0345 <+37>: mov %r14,%rdi 0xff...0348 <+40>: mov %ebp,%esi 0xff...034a <+42>: mov %rbx,%rdx 0xff...034d <+45>: call 0xff...2e0 <__x86_indirect_thunk_array+352> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Indirect calls that use retpolines leading to overhead, not just due to extra instruction but also branch misses. 0xff...0352 <+50>: test %eax,%eax 0xff...0354 <+52>: je 0xff...0339 <security_file_ioctl+25> 0xff...0356 <+54>: jmp 0xff...035a <security_file_ioctl+58> 0xff...0358 <+56>: xor %eax,%eax 0xff...035a <+58>: pop %rbx 0xff...035b <+59>: pop %r14 0xff...035d <+61>: pop %r15 0xff...035f <+63>: pop %rbp 0xff...0360 <+64>: jmp 0xff...47c4 <__x86_return_thunk> The indirect calls are not really needed as one knows the addresses of enabled LSM callbacks at boot time and only the order can possibly change at boot time with the lsm= kernel command line parameter. An array of static calls is defined per LSM hook and the static calls are updated at boot time once the order has been determined. With the hook now exposed as a static call, one can see that the retpolines are no longer there and the LSM callbacks are invoked directly: security_file_ioctl: 0xff...0ca0 <+0>: endbr64 0xff...0ca4 <+4>: nopl 0x0(%rax,%rax,1) 0xff...0ca9 <+9>: push %rbp 0xff...0caa <+10>: push %r14 0xff...0cac <+12>: push %rbx 0xff...0cad <+13>: mov %rdx,%rbx 0xff...0cb0 <+16>: mov %esi,%ebp 0xff...0cb2 <+18>: mov %rdi,%r14 0xff...0cb5 <+21>: jmp 0xff...0cc7 <security_file_ioctl+39> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Static key enabled for SELinux 0xffffffff818f0cb7 <+23>: jmp 0xff...0cde <security_file_ioctl+62> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Static key enabled for BPF LSM. This is something that is changed to default to false to avoid the existing side effect issues of BPF LSM [1] in a subsequent patch. 0xff...0cb9 <+25>: xor %eax,%eax 0xff...0cbb <+27>: xchg %ax,%ax 0xff...0cbd <+29>: pop %rbx 0xff...0cbe <+30>: pop %r14 0xff...0cc0 <+32>: pop %rbp 0xff...0cc1 <+33>: cs jmp 0xff...0000 <__x86_return_thunk> 0xff...0cc7 <+39>: endbr64 0xff...0ccb <+43>: mov %r14,%rdi 0xff...0cce <+46>: mov %ebp,%esi 0xff...0cd0 <+48>: mov %rbx,%rdx 0xff...0cd3 <+51>: call 0xff...3230 <selinux_file_ioctl> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Direct call to SELinux. 0xff...0cd8 <+56>: test %eax,%eax 0xff...0cda <+58>: jne 0xff...0cbd <security_file_ioctl+29> 0xff...0cdc <+60>: jmp 0xff...0cb7 <security_file_ioctl+23> 0xff...0cde <+62>: endbr64 0xff...0ce2 <+66>: mov %r14,%rdi 0xff...0ce5 <+69>: mov %ebp,%esi 0xff...0ce7 <+71>: mov %rbx,%rdx 0xff...0cea <+74>: call 0xff...e220 <bpf_lsm_file_ioctl> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Direct call to BPF LSM. 0xff...0cef <+79>: test %eax,%eax 0xff...0cf1 <+81>: jne 0xff...0cbd <security_file_ioctl+29> 0xff...0cf3 <+83>: jmp 0xff...0cb9 <security_file_ioctl+25> 0xff...0cf5 <+85>: endbr64 0xff...0cf9 <+89>: mov %r14,%rdi 0xff...0cfc <+92>: mov %ebp,%esi 0xff...0cfe <+94>: mov %rbx,%rdx 0xff...0d01 <+97>: pop %rbx 0xff...0d02 <+98>: pop %r14 0xff...0d04 <+100>: pop %rbp 0xff...0d05 <+101>: ret 0xff...0d06 <+102>: int3 0xff...0d07 <+103>: int3 0xff...0d08 <+104>: int3 0xff...0d09 <+105>: int3 While this patch uses static_branch_unlikely indicating that an LSM hook is likely to be not present. In most cases this is still a better choice as even when an LSM with one hook is added, empty slots are created for all LSM hooks (especially when many LSMs that do not initialize most hooks are present on the system). There are some hooks that don't use the call_int_hook or call_void_hook. These hooks are updated to use a new macro called lsm_for_each_hook where the lsm_callback is directly invoked as an indirect call. Below are results of the relevant Unixbench system benchmarks with BPF LSM and SELinux enabled with default policies enabled with and without these patches. Benchmark Delta(%): (+ is better) ========================================================================== Execl Throughput +1.9356 File Write 1024 bufsize 2000 maxblocks +6.5953 Pipe Throughput +9.5499 Pipe-based Context Switching +3.0209 Process Creation +2.3246 Shell Scripts (1 concurrent) +1.4975 System Call Overhead +2.7815 System Benchmarks Index Score (Partial Only): +3.4859 In the best case, some syscalls like eventfd_create benefitted to about ~10%. Tested-by: Guenter Roeck <[email protected]> Reviewed-by: Casey Schaufler <[email protected]> Reviewed-by: Kees Cook <[email protected]> Acked-by: Song Liu <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Signed-off-by: KP Singh <[email protected]> Signed-off-by: Paul Moore <[email protected]>
2024-08-22lsm: count the LSMs enabled at compile timeKP Singh2-3/+138
These macros are a clever trick to determine a count of the number of LSMs that are enabled in the config to ascertain the maximum number of static calls that need to be configured per LSM hook. Without this one would need to generate static calls for the total number of LSMs in the kernel (even if they are not compiled) times the number of LSM hooks which ends up being quite wasteful. Tested-by: Guenter Roeck <[email protected]> Suggested-by: Kui-Feng Lee <[email protected]> Suggested-by: Andrii Nakryiko <[email protected]> Reviewed-by: Kees Cook <[email protected]> Reviewed-by: Casey Schaufler <[email protected]> Reviewed-by: John Johansen <[email protected]> Acked-by: Casey Schaufler <[email protected]> Acked-by: Song Liu <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Nacked-by: Tetsuo Handa <[email protected]> Signed-off-by: KP Singh <[email protected]> [PM: added IPE to the count during merge] Signed-off-by: Paul Moore <[email protected]>
2024-08-22thermal: imx: Use the .should_bind() thermal zone callbackRafael J. Wysocki1-14/+6
Make the imx_thermal driver use the .should_bind() thermal zone callback to provide the thermal core with the information on whether or not to bind the given cooling device to the given trip point in the given thermal zone. If it returns 'true', the thermal core will bind the cooling device to the trip and the corresponding unbinding will be taken care of automatically by the core on the removal of the involved thermal zone or cooling device. In the imx_thermal case, it only needs to return 'true' for the passive trip point and it will match any cooling device passed to it, in analogy with the old-style imx_bind() callback function. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22mlxsw: core_thermal: Use the .should_bind() thermal zone callbackRafael J. Wysocki1-84/+31
Make the mlxsw core_thermal driver use the .should_bind() thermal zone callback to provide the thermal core with the information on whether or not to bind the given cooling device to the given trip point in the given thermal zone. If it returns 'true', the thermal core will bind the cooling device to the trip and the corresponding unbinding will be taken care of automatically by the core on the removal of the involved thermal zone or cooling device. It replaces the .bind() and .unbind() thermal zone callbacks (in 3 places) which assumed the same trip points ordering in the driver and in the thermal core (that may not be true any more in the future). The .bind() callbacks used loops over trip point indices to call thermal_zone_bind_cooling_device() for the same cdev (once it had been verified) and all of the trip points, but they passed different 'upper' and 'lower' values to it for each trip. To retain the original functionality, the .should_bind() callbacks need to use the same 'upper' and 'lower' values that would be used by the corresponding .bind() callbacks when they are about to return 'true'. To that end, the 'priv' field of each trip is set during the thermal zone initialization to point to the corresponding 'state' object containing the maximum and minimum cooling states of the cooling device. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Ido Schimmel <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22platform/x86: acerhdf: Use the .should_bind() thermal zone callbackRafael J. Wysocki1-27/+6
Make the acerhdf driver use the .should_bind() thermal zone callback to provide the thermal core with the information on whether or not to bind the given cooling device to the given trip point in the given thermal zone. If it returns 'true', the thermal core will bind the cooling device to the trip and the corresponding unbinding will be taken care of automatically by the core on the removal of the involved thermal zone or cooling device. The previously existing acerhdf_bind() function bound cooling devices to thermal trip point 0 only, so the new callback needs to return 'true' for trip point 0. However, it is straightforward to observe that trip point 0 is an active trip point and the only other trip point in the driver's thermal zone is a critical one, so it is sufficient to return 'true' from that callback if the type of the given trip point is THERMAL_TRIP_ACTIVE. Signed-off-by: Rafael J. Wysocki <[email protected]> Acked-by: Hans de Goede <[email protected]> Tested-by: Peter Kästle <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: core: Unexport thermal_bind_cdev_to_trip() and ↵Rafael J. Wysocki2-14/+4
thermal_unbind_cdev_from_trip() Since thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip() are only called locally in the thermal core now, they can be static, so change their definitions accordingly and drop their headers from the global thermal header file. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Acked-by: Huisong Li <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: ACPI: Use the .should_bind() thermal zone callbackRafael J. Wysocki1-56/+10
Make the ACPI thermal zone driver use the .should_bind() thermal zone callback to provide the thermal core with the information on whether or not to bind the given cooling device to the given trip point in the given thermal zone. If it returns 'true', the thermal core will bind the cooling device to the trip and the corresponding unbinding will be taken care of automatically by the core on the removal of the involved thermal zone or cooling device. This replaces the .bind() and .unbind() thermal zone callbacks which allows the code to be simplified quite significantly while providing the same functionality. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: core: Introduce .should_bind() thermal zone callbackRafael J. Wysocki2-24/+92
The current design of the code binding cooling devices to trip points in thermal zones is convoluted and hard to follow. Namely, a driver that registers a thermal zone can provide .bind() and .unbind() operations for it, which are required to call either thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip(), respectively, or thermal_zone_bind_cooling_device() and thermal_zone_unbind_cooling_device(), respectively, for every relevant trip point and the given cooling device. Moreover, if .bind() is provided and .unbind() is not, the cleanup necessary during the removal of a thermal zone or a cooling device may not be carried out. In other words, the core relies on the thermal zone owners to do the right thing, which is error prone and far from obvious, even though all of that is not really necessary. Specifically, if the core could ask the thermal zone owner, through a special thermal zone callback, whether or not a given cooling device should be bound to a given trip point in the given thermal zone, it might as well carry out all of the binding and unbinding by itself. In particular, the unbinding can be done automatically without involving the thermal zone owner at all because all of the thermal instances associated with a thermal zone or cooling device going away must be deleted regardless. Accordingly, introduce a new thermal zone operation, .should_bind(), that can be invoked by the thermal core for a given thermal zone, trip point and cooling device combination in order to check whether or not the cooling device should be bound to the trip point at hand. It takes an additional cooling_spec argument allowing the thermal zone owner to specify the highest and lowest cooling states of the cooling device and its weight for the given trip point binding. Make the thermal core use this operation, if present, in the absence of .bind() and .unbind(). Note that .should_bind() will be called under the thermal zone lock. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Acked-by: Huisong Li <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: core: Move thermal zone locking out of bind/unbind functionsRafael J. Wysocki2-9/+23
Since thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip() acquire the thermal zone lock, the locking rules for their callers get complicated. In particular, the thermal zone lock cannot be acquired in any code path leading to one of these functions even though it might be useful to do so. To address this, remove the thermal zone locking from both these functions, add lockdep assertions for the thermal zone lock to both of them and make their callers acquire the thermal zone lock instead. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: sysfs: Use the dev argument in instance-related show/storeRafael J. Wysocki1-8/+7
Two sysfs show/store functions for attributes representing thermal instances, trip_point_show() and weight_store(), retrieve the thermal zone pointer from the instance object at hand, but they may also get it from their dev argument, which is more consistent with what the other thermal sysfs functions do, so make them do so. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Acked-by: Huisong Li <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: core: Drop redundant thermal instance checksRafael J. Wysocki1-2/+2
Because the trip and cdev pointers are sufficient to identify a thermal instance holding them unambiguously, drop the additional thermal zone checks from two loops walking the list of thermal instances in a thermal zone. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: core: Rearrange checks in thermal_bind_cdev_to_trip()Rafael J. Wysocki1-12/+4
It is not necessary to look up the thermal zone and the cooling device in the respective global lists to check whether or not they are registered. It is sufficient to check whether or not their respective list nodes are empty for this purpose. Use the above observation to simplify thermal_bind_cdev_to_trip(). In addition, eliminate an unnecessary ternary operator from it. Moreover, add lockdep_assert_held() for thermal_list_lock to it because that lock must be held by its callers when it is running. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: core: Fold two functions into their respective callersRafael J. Wysocki1-36/+19
Fold bind_cdev() into __thermal_cooling_device_register() and bind_tz() into thermal_zone_device_register_with_trips() to reduce code bloat and make it somewhat easier to follow the code flow. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Zhang Rui <[email protected]> Reviewed-by: Daniel Lezcano <[email protected]> Link: https://patch.msgid.link/[email protected]
2024-08-22thermal: Introduce a debugfs-based testing facilityRafael J. Wysocki6-0/+717
Introduce a facility allowing the thermal core functionality to be exercised in a controlled way in order to verify its behavior, without affecting its regular users noticeably. It is based on the idea of preparing thermal zone templates along with their trip points by writing to files in debugfs. When ready, those templates can be used for registering test thermal zones with the thermal core. The temperature of a test thermal zone created this way can be adjusted via debugfs, which also triggers a __thermal_zone_device_update() call for it. By manipulating the temperature of a test thermal zone, one can check if the thermal core reacts to the changes of it as expected. Signed-off-by: Rafael J. Wysocki <[email protected]> Link: https://patch.msgid.link/[email protected] [ rjw: Fixed ordering of kcalloc() arguments ] [ rjw: Fixed debugfs_create_dir() return value checks ] [ rjw: Fixed two kerneldoc comments ] Signed-off-by: Rafael J. Wysocki <[email protected]>
2024-08-22perf annotate-data: Copy back variable types after moveNamhyung Kim3-0/+40
In some cases, compilers don't set the location expression in DWARF precisely. For instance, it may assign a variable to a register after copying it from a different register. Then it should use the register for the new type but still uses the old register. This makes hard to track the type information properly. This is an example I found in __tcp_transmit_skb(). The first argument (sk) of this function is a pointer to sock and there's a variable (tp) for tcp_sock. static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, gfp_t gfp_mask, u32 rcv_nxt) { ... struct tcp_sock *tp; BUG_ON(!skb || !tcp_skb_pcount(skb)); tp = tcp_sk(sk); prior_wstamp = tp->tcp_wstamp_ns; tp->tcp_wstamp_ns = max(tp->tcp_wstamp_ns, tp->tcp_clock_cache); ... So it basically calls tcp_sk(sk) to get the tcp_sock pointer from sk. But it turned out to be the same value because tcp_sock embeds sock as the first member. The sk is located in reg5 (RDI) and tp is in reg3 (RBX). The offset of tcp_wstamp_ns is 0x748 and tcp_clock_cache is 0x750. So you need to use RBX (reg3) to access the fields in the tcp_sock. But the code used RDI (reg5) as it has the same value. $ pahole --hex -C tcp_sock vmlinux | grep -e 748 -e 750 u64 tcp_wstamp_ns; /* 0x748 0x8 */ u64 tcp_clock_cache; /* 0x750 0x8 */ And this is the disassembly of the part of the function. <__tcp_transmit_skb>: ... 44: mov %rdi, %rbx 47: mov 0x748(%rdi), %rsi 4e: mov 0x750(%rdi), %rax 55: cmp %rax, %rsi Because compiler put the debug info to RBX, it only knows RDI is a pointer to sock and accessing those two fields resulted in error due to offset being beyond the type size. ----------------------------------------------------------- find data type for 0x748(reg5) at __tcp_transmit_skb+0x63 CU for net/ipv4/tcp_output.c (die:0x817f543) frame base: cfa=0 fbreg=6 scope: [1/1] (die:81aac3e) bb: [0 - 30] var [0] -0x98(stack) type='struct tcp_out_options' size=0x28 (die:0x81af3df) var [5] reg8 type='unsigned int' size=0x4 (die:0x8180ed6) var [5] reg2 type='unsigned int' size=0x4 (die:0x8180ed6) var [5] reg1 type='int' size=0x4 (die:0x818059e) var [5] reg4 type='struct sk_buff*' size=0x8 (die:0x8181360) var [5] reg5 type='struct sock*' size=0x8 (die:0x8181a0c) <<<--- the first argument ('sk' at %RDI) mov [19] reg8 -> -0xa8(stack) type='unsigned int' size=0x4 (die:0x8180ed6) mov [20] stack canary -> reg0 mov [29] reg0 -> -0x30(stack) stack canary bb: [36 - 3e] mov [36] reg4 -> reg15 type='struct sk_buff*' size=0x8 (die:0x8181360) bb: [44 - 63] mov [44] reg5 -> reg3 type='struct sock*' size=0x8 (die:0x8181a0c) <<<--- calling tcp_sk() var [47] reg3 type='struct tcp_sock*' size=0x8 (die:0x819eead) <<<--- new variable ('tp' at %RBX) var [4e] reg4 type='unsigned long long' size=0x8 (die:0x8180edd) mov [58] reg4 -> -0xc0(stack) type='unsigned long long' size=0x8 (die:0x8180edd) chk [63] reg5 offset=0x748 ok=1 kind=1 (struct sock*) : offset bigger than size <<<--- access with old variable final result: offset bigger than size While it's a fault in the compiler, we could work around this issue by using the type of new variable when it's copied directly. So I've added copied_from field in the register state to track those direct register to register copies. After that new register gets a new type and the old register still has the same type, it'll update (copy it back) the type of the old register. For example, if we can update type of reg5 at __tcp_transmit_skb+0x47, we can find the target type of the instruction at 0x63 like below: ----------------------------------------------------------- find data type for 0x748(reg5) at __tcp_transmit_skb+0x63 ... bb: [44 - 63] mov [44] reg5 -> reg3 type='struct sock*' size=0x8 (die:0x8181a0c) var [47] reg3 type='struct tcp_sock*' size=0x8 (die:0x819eead) var [47] copyback reg5 type='struct tcp_sock*' size=0x8 (die:0x819eead) <<<--- here mov [47] 0x748(reg5) -> reg4 type='unsigned long long' size=0x8 (die:0x8180edd) mov [4e] 0x750(reg5) -> reg0 type='unsigned long long' size=0x8 (die:0x8180edd) mov [58] reg4 -> -0xc0(stack) type='unsigned long long' size=0x8 (die:0x8180edd) chk [63] reg5 offset=0x748 ok=1 kind=1 (struct tcp_sock*) : Good! <<<--- new type found by insn track: 0x748(reg5) type-offset=0x748 final result: type='struct tcp_sock' size=0xa98 (die:0x819eeb2) Signed-off-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Athira Rajeev <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2024-08-22perf annotate-data: Update stack slot for the storeNamhyung Kim1-4/+25
When checking the match variable at the target instruction, it might not have any information if it's a first write to a stack slot. In this case it could spill a register value into the stack so the type info is in the source operand. But currently it's hard to get the operand from the checking function. Let's process the instruction and retry to get the type info from the stack if there's no information already. This is an example of __tcp_transmit_skb(). The instructions are <__tcp_transmit_skb>: 0: nopl 0x0(%rax, %rax, 1) 5: push %rbp 6: mov %rsp, %rbp 9: push %r15 b: push %r14 d: push %r13 f: push %r12 11: push %rbx 12: sub $0x98, %rsp 19: mov %r8d, -0xa8(%rbp) ... It cannot find any variable at -0xa8(%rbp) at this point. ----------------------------------------------------------- find data type for -0xa8(reg6) at __tcp_transmit_skb+0x19 CU for net/ipv4/tcp_output.c (die:0x817f543) frame base: cfa=0 fbreg=6 scope: [1/1] (die:81aac3e) bb: [0 - 19] var [0] -0x98(stack) type='struct tcp_out_options' size=0x28 (die:0x81af3df) var [5] reg8 type='unsigned int' size=0x4 (die:0x8180ed6) var [5] reg2 type='unsigned int' size=0x4 (die:0x8180ed6) var [5] reg1 type='int' size=0x4 (die:0x818059e) var [5] reg4 type='struct sk_buff*' size=0x8 (die:0x8181360) var [5] reg5 type='struct sock*' size=0x8 (die:0x8181a0c) chk [19] reg6 offset=-0xa8 ok=0 kind=0 fbreg : no type information no type information And it was able to find the type after processing the 'mov' instruction. ----------------------------------------------------------- find data type for -0xa8(reg6) at __tcp_transmit_skb+0x19 CU for net/ipv4/tcp_output.c (die:0x817f543) frame base: cfa=0 fbreg=6 scope: [1/1] (die:81aac3e) bb: [0 - 19] var [0] -0x98(stack) type='struct tcp_out_options' size=0x28 (die:0x81af3df) var [5] reg8 type='unsigned int' size=0x4 (die:0x8180ed6) var [5] reg2 type='unsigned int' size=0x4 (die:0x8180ed6) var [5] reg1 type='int' size=0x4 (die:0x818059e) var [5] reg4 type='struct sk_buff*' size=0x8 (die:0x8181360) var [5] reg5 type='struct sock*' size=0x8 (die:0x8181a0c) chk [19] reg6 offset=-0xa8 ok=0 kind=0 fbreg : retry <<<--- here mov [19] reg8 -> -0xa8(stack) type='unsigned int' size=0x4 (die:0x8180ed6) chk [19] reg6 offset=-0xa8 ok=0 kind=0 fbreg : Good! found by insn track: -0xa8(reg6) type-offset=0 final result: type='unsigned int' size=0x4 (die:0x8180ed6) Signed-off-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Athira Rajeev <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>