Thomas, This a refactor work moving the work done by features like seccomp, ptrace, audit and tracepoints out of the TI flags. The reasons are: 1) Scarcity of TI flags in x86 32-bit. 2) TI flags are defined by the architecture, while these features are arch-independent. 3) Community resistance in merging new architecture-independent features as TI flags. The design exposes a new field in struct thread_info that is read at syscall_trace_enter and syscall_work_exit in place of the ti flags. No functional changes is expected from this patchset. The design and organization of this patchset achieves the following goals: 1) SYSCALL_WORK flags are architecture-independent 2) Architectures that are not using the generic entry code can continue to use TI flags transparently and be converted later. 3) Architectures that migrate to the generic entry code are forced to use the new design. 4) x86, since it supports the generic code, is migrated in this patchset. The transparent usage of TIF or SYSCALL_WORK flags is achieved through some macros. Any code outside of the generic entry code is converted to use the flags only through the accessors. The patchset has some transition helpers, in an attempt to simplify the patches converting each of the subsystems separately. I believe this simplifies the review while making the tree bisectable. I tested this by running each of the features in x86. Other architectures were compile tested only. This is based on top of tip/master. A tree with the patches applies can be pulled from https://gitlab.collabora.com/krisman/linux.git -b x86/tif-cleanup-v1 Please, if possible, consider queueing this for the 5.11 merge window, as this is blocking the Syscall User Dispatch work that has been on the list for a while. Gabriel Krisman Bertazi (10): x86: Expose syscall_work field in thread_info kernel: entry: Expose helpers to migrate TIF to SYSCALL_WORK flags kernel: entry: Wire up syscall_work in common entry code seccomp: Migrate to use SYSCALL_WORK flag tracepoints: Migrate to use SYSCALL_WORK flag ptrace: Migrate to use SYSCALL_TRACE flag ptrace: Migrate TIF_SYSCALL_EMU to use SYSCALL_WORK flag audit: Migrate to use SYSCALL_WORK flag kernel: entry: Drop usage of TIF flags in the generic syscall code x86: Reclaim unused x86 TI flags arch/x86/include/asm/thread_info.h | 11 +----- include/asm-generic/syscall.h | 14 ++++---- include/linux/entry-common.h | 44 ++++++++--------------- include/linux/seccomp.h | 2 +- include/linux/thread_info.h | 57 ++++++++++++++++++++++++++++++ include/linux/tracehook.h | 6 ++-- include/trace/syscall.h | 6 ++-- kernel/auditsc.c | 4 +-- kernel/entry/common.c | 45 +++++++++++------------ kernel/fork.c | 8 ++--- kernel/ptrace.c | 16 ++++----- kernel/seccomp.c | 6 ++-- kernel/trace/trace_events.c | 2 +- kernel/tracepoint.c | 4 +-- 14 files changed, 130 insertions(+), 95 deletions(-) -- 2.29.2
