[PATCH v2 8/7] seccomp: Document two-phase seccomp and arch-provided seccomp_data
The description of how arches should implement seccomp filters was still strictly correct, but it failed to describe the newly available optimizations. Signed-off-by: Andy Lutomirski --- I lost this somehow. Here it as an an extra patch. If I end up sending a v3, I'll fold it in. arch/Kconfig | 11 +++ 1 file changed, 11 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index 0eae9df..05d7a8a 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -323,6 +323,17 @@ config HAVE_ARCH_SECCOMP_FILTER results in the system call being skipped immediately. - seccomp syscall wired up + For best performance, an arch should use seccomp_phase1 and + seccomp_phase2 directly. It should call seccomp_phase1 for all + syscalls if TIF_SECCOMP is set, but seccomp_phase1 does not + need to be called from a ptrace-safe context. It must then + call seccomp_phase2 if seccomp_phase1 returns anything other + than SECCOMP_PHASE1_OK or SECCOMP_PHASE1_SKIP. + + As an additional optimization, an arch may provide seccomp_data + directly to seccomp_phase1; this avoids multiple calls + to the syscall_xyz helpers for every syscall. + config SECCOMP_FILTER def_bool y depends on HAVE_ARCH_SECCOMP_FILTER && SECCOMP && NET -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 8/7] seccomp: Document two-phase seccomp and arch-provided seccomp_data
The description of how arches should implement seccomp filters was still strictly correct, but it failed to describe the newly available optimizations. Signed-off-by: Andy Lutomirski l...@amacapital.net --- I lost this somehow. Here it as an an extra patch. If I end up sending a v3, I'll fold it in. arch/Kconfig | 11 +++ 1 file changed, 11 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index 0eae9df..05d7a8a 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -323,6 +323,17 @@ config HAVE_ARCH_SECCOMP_FILTER results in the system call being skipped immediately. - seccomp syscall wired up + For best performance, an arch should use seccomp_phase1 and + seccomp_phase2 directly. It should call seccomp_phase1 for all + syscalls if TIF_SECCOMP is set, but seccomp_phase1 does not + need to be called from a ptrace-safe context. It must then + call seccomp_phase2 if seccomp_phase1 returns anything other + than SECCOMP_PHASE1_OK or SECCOMP_PHASE1_SKIP. + + As an additional optimization, an arch may provide seccomp_data + directly to seccomp_phase1; this avoids multiple calls + to the syscall_xyz helpers for every syscall. + config SECCOMP_FILTER def_bool y depends on HAVE_ARCH_SECCOMP_FILTER SECCOMP NET -- 1.9.3 -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
