Re: Boot failures with "mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER" on powerpc (was Re: mmotm 2018-07-10-16-50 uploaded)
From: Oscar Salvador <hidden>
Date: 2018-07-12 09:50:02
Also in:
linux-fsdevel, linux-mm, linux-next, lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Possibly related (same subject, not in this thread)
- 2018-07-12 · Re: Boot failures with "mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER" on powerpc (was Re: mmotm 2018-07-10-16-50 uploaded) · Stephen Rothwell <hidden>
- 2018-07-12 · Re: Boot failures with "mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER" on powerpc (was Re: mmotm 2018-07-10-16-50 uploaded) · Michael Ellerman <mpe@ellerman.id.au>
- 2018-07-12 · Re: Boot failures with "mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER" on powerpc (was Re: mmotm 2018-07-10-16-50 uploaded) · Michael Ellerman <mpe@ellerman.id.au>
- 2018-07-11 · Re: Boot failures with "mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER" on powerpc (was Re: mmotm 2018-07-10-16-50 uploaded) · Stephen Rothwell <hidden>
- 2018-07-11 · Re: Boot failures with "mm/sparse: Remove CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER" on powerpc (was Re: mmotm 2018-07-10-16-50 uploaded) · Andrew Morton <akpm@linux-foundation.org>
quoted
I just roughly check, but if I checked the right place, vmemmap_populated() checks for the section to contain the flags we are setting in sparse_init_one_section().Yes.quoted
But with this patch, we populate first everything, and then we call sparse_init_one_section() in sparse_init(). As I said I could be mistaken because I just checked the surface.Yeah I think that's correct. This might just be a bug in our code, let me look at it a bit.
I wonder if something like this could make the trick:
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index 51ce091914f9..e281651f50cd 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c@@ -177,6 +177,8 @@ static __meminit void vmemmap_list_populate(unsigned long phys, vmemmap_list = vmem_back; } +static unsigned long last_addr_populated = 0; + int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) {
@@ -191,7 +193,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, void *p; int rc; - if (vmemmap_populated(start, page_size)) + if (start + page_size <= last_addr_populated) continue; if (altmap)
@@ -212,6 +214,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, __func__, rc); return -EFAULT; } + last_addr_populated = start + page_size; }
I know it looks hacky, and chances are that are wrong, but could you give it a try? I will try to grab a ppc server and try it out too. Thanks -- Oscar Salvador SUSE L3