On Aug 9, 2016 11:30 PM, "Chris Metcalf" <[email protected]> wrote: > > In exit_to_usermode_loop(), call task_isolation_ready() for > TIF_TASK_ISOLATION tasks when we are checking the thread-info flags, > and after we've handled the other work, call task_isolation_enter() > for such tasks. > > In syscall_trace_enter_phase1(), we add the necessary support for > reporting syscalls for task-isolation processes. > > We add strict reporting for the kernel exception types that do > not result in signals, namely non-signalling page faults and > non-signalling MPX fixups. > > Tested-by: Christoph Lameter <[email protected]> > Signed-off-by: Chris Metcalf <[email protected]> > --- > arch/x86/Kconfig | 1 + > arch/x86/entry/common.c | 20 +++++++++++++++++++- > arch/x86/include/asm/thread_info.h | 2 ++ > arch/x86/kernel/smp.c | 2 ++ > arch/x86/kernel/traps.c | 3 +++ > arch/x86/mm/fault.c | 5 +++++ > 6 files changed, 32 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 5c6e7471b732..10b2c0567dad 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -89,6 +89,7 @@ config X86 > select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT > select HAVE_ARCH_SECCOMP_FILTER > select HAVE_ARCH_SOFT_DIRTY if X86_64 > + select HAVE_ARCH_TASK_ISOLATION > select HAVE_ARCH_TRACEHOOK > select HAVE_ARCH_TRANSPARENT_HUGEPAGE > select HAVE_EBPF_JIT if X86_64 > diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c > index 1433f6b4607d..5c1b9fc89bf2 100644 > --- a/arch/x86/entry/common.c > +++ b/arch/x86/entry/common.c > @@ -21,6 +21,7 @@ > #include <linux/context_tracking.h> > #include <linux/user-return-notifier.h> > #include <linux/uprobes.h> > +#include <linux/isolation.h> > > #include <asm/desc.h> > #include <asm/traps.h> > @@ -91,6 +92,15 @@ static long syscall_trace_enter(struct pt_regs *regs) > if (emulated) > return -1L; > > + /* In isolation mode, we may prevent the syscall from running. */ > + if (work & _TIF_TASK_ISOLATION) { > + if (task_isolation_syscall(regs->orig_ax) == -1) { > + regs->orig_ax = -1; > + return 0; > + } > + work &= ~_TIF_TASK_ISOLATION; > + } > +
What is this? It's not mentioned in the changelog. It seems nonsensical to me. If nothing else, you forgot to update regs->ax, but I don't even know what you're trying to do. > #ifdef CONFIG_SECCOMP > /* > * Do seccomp after ptrace, to catch any tracer changes. > @@ -136,7 +146,7 @@ static long syscall_trace_enter(struct pt_regs *regs) > > #define EXIT_TO_USERMODE_LOOP_FLAGS \ > (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ > - _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY) > + _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY | _TIF_TASK_ISOLATION) > Where are you updating the conditions to force use of the slow path? (That's _TIF_ALLWORK_MASK.) --Andy
