On Mon, Aug 26, 2019 at 10:08:26PM +0200, Christophe Leroy wrote:
>
>
> Le 26/08/2019 à 18:50, Greg Kroah-Hartman a écrit :
> > On Wed, Aug 21, 2019 at 10:19:27AM +1000, Alastair D'Silva wrote:
> > > From: Alastair D'Silva <alast...@d-silva.org>
> > >
> > > The upstream commit:
> > > 22e9c88d486a ("powerpc/64: reuse PPC32 static inline
> > > flush_dcache_range()")
> > > has a similar effect, but since it is a rewrite of the assembler to C, is
> > > too invasive for stable. This patch is a minimal fix to address the issue
> > > in
> > > assembler.
> > >
> > > This patch applies cleanly to v5.2, v4.19 & v4.14.
> > >
> > > When calling flush_(inval_)dcache_range with a size >4GB, we were masking
> > > off the upper 32 bits, so we would incorrectly flush a range smaller
> > > than intended.
> > >
> > > This patch replaces the 32 bit shifts with 64 bit ones, so that
> > > the full size is accounted for.
> > >
> > > Changelog:
> > > v2
> > > - Add related upstream commit
> > >
> > > Signed-off-by: Alastair D'Silva <alast...@d-silva.org>
> > > ---
> > > arch/powerpc/kernel/misc_64.S | 4 ++--
> > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
> > > index 1ad4089dd110..d4d096f80f4b 100644
> > > --- a/arch/powerpc/kernel/misc_64.S
> > > +++ b/arch/powerpc/kernel/misc_64.S
> > > @@ -130,7 +130,7 @@ _GLOBAL_TOC(flush_dcache_range)
> > > subf r8,r6,r4 /* compute length */
> > > add r8,r8,r5 /* ensure we get enough */
> > > lwz r9,DCACHEL1LOGBLOCKSIZE(r10) /* Get log-2 of dcache
> > > block size */
> > > - srw. r8,r8,r9 /* compute line count */
> > > + srd. r8,r8,r9 /* compute line count */
> > > beqlr /* nothing to do? */
> > > mtctr r8
> > > 0: dcbst 0,r6
> > > @@ -148,7 +148,7 @@ _GLOBAL(flush_inval_dcache_range)
> > > subf r8,r6,r4 /* compute length */
> > > add r8,r8,r5 /* ensure we get enough */
> > > lwz r9,DCACHEL1LOGBLOCKSIZE(r10)/* Get log-2 of dcache
> > > block size */
> > > - srw. r8,r8,r9 /* compute line count */
> > > + srd. r8,r8,r9 /* compute line count */
> > > beqlr /* nothing to do? */
> > > sync
> > > isync
> >
> > I need an ack from the powerpc maintainer(s) before I can take this.
>
> I think you already got an ack (on v1). See
> https://patchwork.ozlabs.org/patch/1147403/#2239663
How am I supposed to remember that? :)
greg k-h
