powerpc: Allow flush_icache_range to work across ranges >4GB

commit 29430fae82073d39b1b881a3cd507416a56a363f upstream.

When calling flush_icache_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.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191104023305.9581-2-alastair@au1.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 1bf6aae..facc029 100644 (file)
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -87,7 +87,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
        subf    r8,r6,r4                /* compute length */
        add     r8,r8,r5                /* ensure we get enough */
        lwz     r9,DCACHEL1LOGBLOCKSIZE(r10)    /* Get log-2 of cache block size */
-       srw.    r8,r8,r9                /* compute line count */
+       srd.    r8,r8,r9                /* compute line count */
        beqlr                           /* nothing to do? */
        mtctr   r8
 1:     dcbst   0,r6
@@ -103,7 +103,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
        subf    r8,r6,r4                /* compute length */
        add     r8,r8,r5
        lwz     r9,ICACHEL1LOGBLOCKSIZE(r10)    /* Get log-2 of Icache block size */
-       srw.    r8,r8,r9                /* compute line count */
+       srd.    r8,r8,r9                /* compute line count */
        beqlr                           /* nothing to do? */
        mtctr   r8
 2:     icbi    0,r6