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    SubjectRe: [PATCH 1/3] hvc_dcc: Fix bad code generation by marking assembly volatile
    Hi!

    > > diff --git a/drivers/char/hvc_dcc.c b/drivers/char/hvc_dcc.c
    > > index 6470f63..155ec10 100644
    > > --- a/drivers/char/hvc_dcc.c
    > > +++ b/drivers/char/hvc_dcc.c
    > > @@ -33,8 +33,7 @@
    > > static inline u32 __dcc_getstatus(void)
    > > {
    > > u32 __ret;
    > > -
    > > - asm("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg"
    > > + asm volatile("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg"
    > > : "=r" (__ret) : : "cc");
    > >
    > > return __ret;

    Is volatile needed here? If __dcc_getstatus() return value is
    discarded, we want assembly discarded, right?


    > > @@ -58,7 +57,7 @@ static inline char __dcc_getchar(void)
    > > {
    > > char __c;
    > >
    > > - asm("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
    > > + asm volatile("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
    > > : "=r" (__c));
    > >
    > > return __c;

    Same here?
    Pavel
    --
    (english) http://www.livejournal.com/~pavelmachek
    (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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