| From bd7069008557a9f24bfcaa6159841be9da202074 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 6 May 2021 18:05:16 -0700 |
| Subject: kernel/resource: make walk_mem_res() find all busy IORESOURCE_MEM |
| resources |
| |
| From: David Hildenbrand <david@redhat.com> |
| |
| [ Upstream commit 3c9c797534364593b73ba6ab060a014af8934721 ] |
| |
| It used to be true that we can have system RAM (IORESOURCE_SYSTEM_RAM | |
| IORESOURCE_BUSY) only on the first level in the resource tree. However, |
| this is no longer holds for driver-managed system RAM (i.e., added via |
| dax/kmem and virtio-mem), which gets added on lower levels, for example, |
| inside device containers. |
| |
| IORESOURCE_SYSTEM_RAM is defined as IORESOURCE_MEM | IORESOURCE_SYSRAM and |
| just a special type of IORESOURCE_MEM. |
| |
| The function walk_mem_res() only considers the first level and is used in |
| arch/x86/mm/ioremap.c:__ioremap_check_mem() only. We currently fail to |
| identify System RAM added by dax/kmem and virtio-mem as |
| "IORES_MAP_SYSTEM_RAM", for example, allowing for remapping of such |
| "normal RAM" in __ioremap_caller(). |
| |
| Let's find all IORESOURCE_MEM | IORESOURCE_BUSY resources, making the |
| function behave similar to walk_system_ram_res(). |
| |
| Link: https://lkml.kernel.org/r/20210325115326.7826-3-david@redhat.com |
| Fixes: ebf71552bb0e ("virtio-mem: Add parent resource for all added "System RAM"") |
| Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM") |
| Signed-off-by: David Hildenbrand <david@redhat.com> |
| Reviewed-by: Dan Williams <dan.j.williams@intel.com> |
| Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Cc: Dan Williams <dan.j.williams@intel.com> |
| Cc: Daniel Vetter <daniel.vetter@ffwll.ch> |
| Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> |
| Cc: Dave Young <dyoung@redhat.com> |
| Cc: Baoquan He <bhe@redhat.com> |
| Cc: Vivek Goyal <vgoyal@redhat.com> |
| Cc: Dave Hansen <dave.hansen@linux.intel.com> |
| Cc: Keith Busch <keith.busch@intel.com> |
| Cc: Michal Hocko <mhocko@suse.com> |
| Cc: Qian Cai <cai@lca.pw> |
| Cc: Oscar Salvador <osalvador@suse.de> |
| Cc: Eric Biederman <ebiederm@xmission.com> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Cc: Ingo Molnar <mingo@redhat.com> |
| Cc: Borislav Petkov <bp@alien8.de> |
| Cc: "H. Peter Anvin" <hpa@zytor.com> |
| Cc: Tom Lendacky <thomas.lendacky@amd.com> |
| Cc: Brijesh Singh <brijesh.singh@amd.com> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| kernel/resource.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| diff --git a/kernel/resource.c b/kernel/resource.c |
| index 88a0ed866777..817545ff80b9 100644 |
| --- a/kernel/resource.c |
| +++ b/kernel/resource.c |
| @@ -463,7 +463,7 @@ int walk_mem_res(u64 start, u64 end, void *arg, |
| { |
| unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
| |
| - return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, true, |
| + return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, false, |
| arg, func); |
| } |
| |
| -- |
| 2.30.2 |
| |