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.
We have two users of walk_system_ram_res(), which currently only consideres the first level: a) kernel/kexec_file.c:kexec_walk_resources() -- We properly skip IORESOURCE_SYSRAM_DRIVER_MANAGED resources via locate_mem_hole_callback(), so even after this change, we won't be placing kexec images onto dax/kmem and virtio-mem added memory. No change. b) arch/x86/kernel/crash.c:fill_up_crash_elf_data() -- we're currently not adding relevant ranges to the crash elf header, resulting in them not getting dumped via kdump. This change fixes loading a crashkernel via kexec_file_load() and including dax/kmem and virtio-mem added System RAM in the crashdump on x86-64. Note that e.g,, arm64 relies on memblock data and, therefore, always considers all added System RAM already. Let's find all IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY resources, making the function behave like walk_system_ram_range(). Fixes: ebf71552bb0e ("virtio-mem: Add parent resource for all added "System RAM"") Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM") Reviewed-by: Dan Williams <dan.j.willi...@intel.com> Acked-by: Baoquan He <b...@redhat.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Dan Williams <dan.j.willi...@intel.com> Cc: Daniel Vetter <daniel.vet...@ffwll.ch> Cc: Andy Shevchenko <andriy.shevche...@linux.intel.com> Cc: Mauro Carvalho Chehab <mchehab+hua...@kernel.org> Cc: Dave Young <dyo...@redhat.com> Cc: Baoquan He <b...@redhat.com> Cc: Vivek Goyal <vgo...@redhat.com> Cc: Dave Hansen <dave.han...@linux.intel.com> Cc: Keith Busch <keith.bu...@intel.com> Cc: Michal Hocko <mho...@suse.com> Cc: Qian Cai <c...@lca.pw> Cc: Oscar Salvador <osalva...@suse.de> Cc: Eric Biederman <ebied...@xmission.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Ingo Molnar <mi...@redhat.com> Cc: Borislav Petkov <b...@alien8.de> Cc: "H. Peter Anvin" <h...@zytor.com> Cc: Tom Lendacky <thomas.lenda...@amd.com> Cc: Brijesh Singh <brijesh.si...@amd.com> Cc: x...@kernel.org Cc: kexec@lists.infradead.org Signed-off-by: David Hildenbrand <da...@redhat.com> --- kernel/resource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/resource.c b/kernel/resource.c index 627e61b0c124..4efd6e912279 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -457,7 +457,7 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, { unsigned long flags = IORESOURCE_SYSTEM_RAM | 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); } -- 2.29.2 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec