From: Dave Hansen <dave.hansen@linux.intel.com> mainline inclusion from mainline-v5.1-rc1 commit 2b539aefe9e48e3908cff02699aa63a8b9bd268e category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I47H3V CVE: NA -------------------------------- In the process of onlining memory, we use walk_system_ram_range() to find the actual RAM areas inside of the area being onlined. However, it currently only finds memory resources which are "top-level" iomem_resources. Children are not currently searched which causes it to skip System RAM in areas like this (in the format of /proc/iomem): a0000000-bfffffff : Persistent Memory (legacy) a0000000-afffffff : System RAM Changing the true->false here allows children to be searched as well. We need this because we add a new "System RAM" resource underneath the "persistent memory" resource when we use persistent memory in a volatile mode. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ross Zwisler <zwisler@kernel.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: linux-nvdimm@lists.01.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: Huang Ying <ying.huang@intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jackie Liu <liuyun01@kylinos.cn> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- kernel/resource.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/resource.c b/kernel/resource.c index 2cf0edd8223f2..55a3c60106827 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -448,6 +448,9 @@ int walk_mem_res(u64 start, u64 end, void *arg, * This function calls the @func callback against all memory ranges of type * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. * It is to be used only for System RAM. + * + * This will find System RAM ranges that are children of top-level resources + * in addition to top-level System RAM resources. */ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)) @@ -463,7 +466,7 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; while (start < end && !find_next_iomem_res(start, end, flags, IORES_DESC_NONE, - true, &res)) { + false, &res)) { pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; end_pfn = (res.end + 1) >> PAGE_SHIFT; if (end_pfn > pfn) -- 2.25.1