On 1/11/19 7:54 AM, Tycho Andersen wrote: > On Thu, Jan 10, 2019 at 02:09:39PM -0700, Khalid Aziz wrote: >> From: Juerg Haefliger <[email protected]> >> >> If the page is unmapped by XPFO, a data cache flush results in a fatal >> page fault, so let's temporarily map the region, flush the cache, and then >> unmap it. >> >> v6: actually flush in the face of xpfo, and temporarily map the underlying >> memory so it can be flushed correctly >> >> CC: [email protected] >> Signed-off-by: Juerg Haefliger <[email protected]> >> Signed-off-by: Tycho Andersen <[email protected]> >> Signed-off-by: Khalid Aziz <[email protected]> >> --- >> arch/arm64/mm/flush.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c >> index 30695a868107..f12f26b60319 100644 >> --- a/arch/arm64/mm/flush.c >> +++ b/arch/arm64/mm/flush.c >> @@ -20,6 +20,7 @@ >> #include <linux/export.h> >> #include <linux/mm.h> >> #include <linux/pagemap.h> >> +#include <linux/xpfo.h> >> >> #include <asm/cacheflush.h> >> #include <asm/cache.h> >> @@ -28,9 +29,15 @@ >> void sync_icache_aliases(void *kaddr, unsigned long len) >> { >> unsigned long addr = (unsigned long)kaddr; >> + unsigned long num_pages = XPFO_NUM_PAGES(addr, len); >> + void *mapping[num_pages]; > > Does this still compile with -Wvla? It was a bad hack on my part, and > we should probably just drop it and come up with something else :)
I will make a note of it. I hope someone with better knowledge of arm64
than me can come up with a better solution ;)
--
Khalid
>
> Tycho
>
>> if (icache_is_aliasing()) {
>> + xpfo_temp_map(kaddr, len, mapping,
>> + sizeof(mapping[0]) * num_pages);
>> __clean_dcache_area_pou(kaddr, len);
>> + xpfo_temp_unmap(kaddr, len, mapping,
>> + sizeof(mapping[0]) * num_pages);
>> __flush_icache_all();
>> } else {
>> flush_icache_range(addr, addr + len);
>> --
>> 2.17.1
>>
pEpkey.asc
Description: application/pgp-keys
