Re: [RFC PATCH 3/4] x86/traps: Attempt to fixup exceptions in vDSO before signaling

2018-12-06 Thread Andy Lutomirski
On Thu, Dec 6, 2018 at 10:22 AM Dave Hansen wrote: > > On 12/5/18 3:20 PM, Sean Christopherson wrote: > > @@ -223,6 +224,10 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, > > const char *str, > > tsk->thread.error_code = error_code; > > tsk->thread.trap_nr = trapnr; > > > >

Re: [RFC PATCH 3/4] x86/traps: Attempt to fixup exceptions in vDSO before signaling

2018-12-06 Thread Dave Hansen
On 12/5/18 3:20 PM, Sean Christopherson wrote: > @@ -223,6 +224,10 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, > const char *str, > tsk->thread.error_code = error_code; > tsk->thread.trap_nr = trapnr; > > + if (user_mode(regs) && > + fixup_vdso_exception(reg

[RFC PATCH 3/4] x86/traps: Attempt to fixup exceptions in vDSO before signaling

2018-12-05 Thread Sean Christopherson
Call fixup_vdso_exception() to attempt to fixup exceptions in vDSO code before generating a signal for userspace faults. This allows vDSO functions to utilize exception fixup to report unhandled exceptions directly to userspace for specific flows in lieu of generating a signal. Suggested-by: And