From: "Aneesh Kumar K.V" aneesh.kumar@linux.ibm.com
[ Upstream commit ccaea15296f9773abd43aaa17ee4b88848e4a505 ]
If we fail to allocate vmemmap list, we don't keep track of allocated vmemmap block buf. Hence on section deactivate we skip vmemmap block buf free. This results in memory leak.
Signed-off-by: Aneesh Kumar K.V aneesh.kumar@linux.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20200731113500.248306-1-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/mm/init_64.c | 35 ++++++++++++++++++++++++++++------- 1 file changed, 28 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c index 8459056cce671..2ae42c2a5cf04 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -162,16 +162,16 @@ static __meminit struct vmemmap_backing * vmemmap_list_alloc(int node) return next++; }
-static __meminit void vmemmap_list_populate(unsigned long phys, - unsigned long start, - int node) +static __meminit int vmemmap_list_populate(unsigned long phys, + unsigned long start, + int node) { struct vmemmap_backing *vmem_back;
vmem_back = vmemmap_list_alloc(node); if (unlikely(!vmem_back)) { - WARN_ON(1); - return; + pr_debug("vmemap list allocation failed\n"); + return -ENOMEM; }
vmem_back->phys = phys; @@ -179,6 +179,7 @@ static __meminit void vmemmap_list_populate(unsigned long phys, vmem_back->list = vmemmap_list;
vmemmap_list = vmem_back; + return 0; }
static bool altmap_cross_boundary(struct vmem_altmap *altmap, unsigned long start, @@ -199,6 +200,7 @@ static bool altmap_cross_boundary(struct vmem_altmap *altmap, unsigned long star int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) { + bool altmap_alloc; unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
/* Align to the page size of the linear mapping. */ @@ -228,13 +230,32 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, p = vmemmap_alloc_block_buf(page_size, node, altmap); if (!p) pr_debug("altmap block allocation failed, falling back to system memory"); + else + altmap_alloc = true; } - if (!p) + if (!p) { p = vmemmap_alloc_block_buf(page_size, node, NULL); + altmap_alloc = false; + } if (!p) return -ENOMEM;
- vmemmap_list_populate(__pa(p), start, node); + if (vmemmap_list_populate(__pa(p), start, node)) { + /* + * If we don't populate vmemap list, we don't have + * the ability to free the allocated vmemmap + * pages in section_deactivate. Hence free them + * here. + */ + int nr_pfns = page_size >> PAGE_SHIFT; + unsigned long page_order = get_order(page_size); + + if (altmap_alloc) + vmem_altmap_free(altmap, nr_pfns); + else + free_pages((unsigned long)p, page_order); + return -ENOMEM; + }
pr_debug(" * %016lx..%016lx allocated at %p\n", start, start + page_size, p);