From bc0d0d093b379b0b379c429e3348498287c8a9ca Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 30 Nov 2015 09:10:33 -0800 Subject: [PATCH] libnvdimm, e820: skip module loading when no type-12 If there are no persistent memory ranges present then don't bother creating the platform device. Otherwise, it loads the full libnvdimm sub-system only to discover no resources present. Reported-by: Andy Lutomirski Acked-by: Andy Lutomirski Signed-off-by: Dan Williams --- arch/x86/kernel/pmem.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/x86/kernel/pmem.c b/arch/x86/kernel/pmem.c index 4f00b63d7ff3..14415aff1813 100644 --- a/arch/x86/kernel/pmem.c +++ b/arch/x86/kernel/pmem.c @@ -4,10 +4,22 @@ */ #include #include +#include + +static int found(u64 start, u64 end, void *data) +{ + return 1; +} static __init int register_e820_pmem(void) { + char *pmem = "Persistent Memory (legacy)"; struct platform_device *pdev; + int rc; + + rc = walk_iomem_res(pmem, IORESOURCE_MEM, 0, -1, NULL, found); + if (rc <= 0) + return 0; /* * See drivers/nvdimm/e820.c for the implementation, this is -- 2.20.1