Right now, ZONE_DEVICE memory is always set PG_reserved. We want to change that. We could explicitly check for is_zone_device_page(page). But looking at the pfn_valid() check, it seems safer to just use pfn_to_online_page() here, that will skip all ZONE_DEVICE pages right away. Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> --- arch/x86/mm/ioremap.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index a39dcdb5ae34..db6913b48edf 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -77,10 +77,17 @@ static unsigned int __ioremap_check_ram(struct resource *res) start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT; stop_pfn = (res->end + 1) >> PAGE_SHIFT; if (stop_pfn > start_pfn) { - for (i = 0; i < (stop_pfn - start_pfn); ++i) - if (pfn_valid(start_pfn + i) && - !PageReserved(pfn_to_page(start_pfn + i))) + for (i = 0; i < (stop_pfn - start_pfn); ++i) { + struct page *page; + /* + * We treat any pages that are not online (not managed + * by the buddy) as not being RAM. This includes + * ZONE_DEVICE pages. + */ + page = pfn_to_online_page(start_pfn + i); + if (page && !PageReserved(page)) return IORES_MAP_SYSTEM_RAM; + } } return 0; -- 2.21.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel