From b7c5f9a1fb9b40491d8b564b7eb9df26128cda3f Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Tue, 15 Oct 2024 13:15:54 +0800 Subject: [PATCH] resource: remove dependency on SPARSEMEM from GET_FREE_REGION We want to use the functions (get_free_mem_region()) configured via GET_FREE_REGION in resource kunit tests. However, GET_FREE_REGION depends on SPARSEMEM now. This makes resource kunit tests cannot be built on some architectures lacking SPARSEMEM, or causes config warning as follows, WARNING: unmet direct dependencies detected for GET_FREE_REGION Depends on [n]: SPARSEMEM [=n] Selected by [y]: - RESOURCE_KUNIT_TEST [=y] && RUNTIME_TESTING_MENU [=y] && KUNIT [=y] When get_free_mem_region() was introduced the only consumers were those looking to pass the address range to memremap_pages(). That address range needed to be mindful of the maximum addressable platform physical address which at the time only SPARSMEM defined via MAX_PHYSMEM_BITS. Given that memremap_pages() also depended on SPARSEMEM via ZONE_DEVICE, it was easier to just depend on that definition than invent a general MAX_PHYSMEM_BITS concept outside of SPARSEMEM. Turns out that decision was buggy and did not account for KASAN consumption of physical address space. That problem was resolved recently with commit ea72ce5da228 ("x86/kaslr: Expose and use the end of the physical memory address space"), and GET_FREE_REGION dropped its MAX_PHYSMEM_BITS dependency. Then commit 99185c10d5d9 ("resource, kunit: add test case for region_intersects()"), went ahead and fixed up the only remaining dependency on SPARSEMEM which was usage of the PA_SECTION_SHIFT macro for setting the default alignment. A PAGE_SIZE fallback is fine in the SPARSEMEM=n case. With those build dependencies gone GET_FREE_REGION no longer depends on SPARSEMEM. So, the patch removes dependency on SPARSEMEM from GET_FREE_REGION to fix the build issues. Link: https://lkml.kernel.org/r/20241016014730.339369-1-ying.huang@intel.com Link: https://lore.kernel.org/lkml/20240922225041.603186-1-linux@roeck-us.net/ Link: https://lkml.kernel.org/r/20241015051554.294734-1-ying.huang@intel.com Fixes: 99185c10d5d9 ("resource, kunit: add test case for region_intersects()") Signed-off-by: "Huang, Ying" Co-developed-by: Dan Williams Signed-off-by: Dan Williams Tested-by: Guenter Roeck Acked-by: David Hildenbrand Tested-by: Nathan Chancellor # build Cc: Arnd Bergmann Cc: Jonathan Cameron Signed-off-by: Andrew Morton --- mm/Kconfig | 1 - 1 file changed, 1 deletion(-) diff --git a/mm/Kconfig b/mm/Kconfig index 4c9f5ea13271..33fa51d608dc 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -1085,7 +1085,6 @@ config HMM_MIRROR depends on MMU config GET_FREE_REGION - depends on SPARSEMEM bool config DEVICE_PRIVATE