Re: [PATCH v2 5/7] x86: plumb error code and fault address through to fault handlers
On Mon, Aug 27, 2018 at 9:09 PM Andy Lutomirski wrote:
>
> On Mon, Aug 27, 2018 at 11:56 AM, Jann Horn wrote:
> > This is preparation for looking at trap number and fault address in the
> > handlers for uaccess errors.
> > This patch should not change any behavior.
>
> Confused. $SUBJECT says you're plumbing the error code through, and
> you are sort of doing it:
>
> > -int fixup_exception(struct pt_regs *regs, int trapnr)
> > +int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long
> > error_code,
> > + unsigned long fault_addr)
> > {
>
> It's available here...
>
> > const struct exception_table_entry *e;
> > ex_handler_t handler;
> > @@ -202,7 +212,7 @@ int fixup_exception(struct pt_regs *regs, int trapnr)
> > return 0;
> >
> > handler = ex_fixup_handler(e);
> > - return handler(e, regs, trapnr);
> > + return handler(e, regs, trapnr, fault_addr);
>
> ... but you don't pass it into the handlers. Is this intentional?
Whoops. No, that's not intentional. I'll fix it up for the next version.
Re: [PATCH v2 5/7] x86: plumb error code and fault address through to fault handlers
On Mon, Aug 27, 2018 at 9:09 PM Andy Lutomirski wrote:
>
> On Mon, Aug 27, 2018 at 11:56 AM, Jann Horn wrote:
> > This is preparation for looking at trap number and fault address in the
> > handlers for uaccess errors.
> > This patch should not change any behavior.
>
> Confused. $SUBJECT says you're plumbing the error code through, and
> you are sort of doing it:
>
> > -int fixup_exception(struct pt_regs *regs, int trapnr)
> > +int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long
> > error_code,
> > + unsigned long fault_addr)
> > {
>
> It's available here...
>
> > const struct exception_table_entry *e;
> > ex_handler_t handler;
> > @@ -202,7 +212,7 @@ int fixup_exception(struct pt_regs *regs, int trapnr)
> > return 0;
> >
> > handler = ex_fixup_handler(e);
> > - return handler(e, regs, trapnr);
> > + return handler(e, regs, trapnr, fault_addr);
>
> ... but you don't pass it into the handlers. Is this intentional?
Whoops. No, that's not intentional. I'll fix it up for the next version.
Re: [PATCH v2 5/7] x86: plumb error code and fault address through to fault handlers
On Mon, Aug 27, 2018 at 11:56 AM, Jann Horn wrote:
> This is preparation for looking at trap number and fault address in the
> handlers for uaccess errors.
> This patch should not change any behavior.
Confused. $SUBJECT says you're plumbing the error code through, and
you are sort of doing it:
> -int fixup_exception(struct pt_regs *regs, int trapnr)
> +int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long
> error_code,
> + unsigned long fault_addr)
> {
It's available here...
> const struct exception_table_entry *e;
> ex_handler_t handler;
> @@ -202,7 +212,7 @@ int fixup_exception(struct pt_regs *regs, int trapnr)
> return 0;
>
> handler = ex_fixup_handler(e);
> - return handler(e, regs, trapnr);
> + return handler(e, regs, trapnr, fault_addr);
... but you don't pass it into the handlers. Is this intentional?
Re: [PATCH v2 5/7] x86: plumb error code and fault address through to fault handlers
On Mon, Aug 27, 2018 at 11:56 AM, Jann Horn wrote:
> This is preparation for looking at trap number and fault address in the
> handlers for uaccess errors.
> This patch should not change any behavior.
Confused. $SUBJECT says you're plumbing the error code through, and
you are sort of doing it:
> -int fixup_exception(struct pt_regs *regs, int trapnr)
> +int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long
> error_code,
> + unsigned long fault_addr)
> {
It's available here...
> const struct exception_table_entry *e;
> ex_handler_t handler;
> @@ -202,7 +212,7 @@ int fixup_exception(struct pt_regs *regs, int trapnr)
> return 0;
>
> handler = ex_fixup_handler(e);
> - return handler(e, regs, trapnr);
> + return handler(e, regs, trapnr, fault_addr);
... but you don't pass it into the handlers. Is this intentional?
