Re: [PATCH v2 1/2] mm: cma: allocate cma areas bottom-up

[Andrew Morton]

On Mon, 21 Dec 2020 09:05:51 -0800 Roman Gushchin <guro@xxxxxx> wrote:

> Subject: [PATCH v3 1/2] mm: cma: allocate cma areas bottom-up

i386 allmodconfig:

In file included from ./include/vdso/const.h:5,
                 from ./include/linux/const.h:4,
                 from ./include/linux/bits.h:5,
                 from ./include/linux/bitops.h:6,
                 from ./include/linux/kernel.h:11,
                 from ./include/asm-generic/bug.h:20,
                 from ./arch/x86/include/asm/bug.h:93,
                 from ./include/linux/bug.h:5,
                 from ./include/linux/mmdebug.h:5,
                 from ./include/linux/mm.h:9,
                 from ./include/linux/memblock.h:13,
                 from mm/cma.c:24:
mm/cma.c: In function ‘cma_declare_contiguous_nid’:
./include/uapi/linux/const.h:20:19: warning: conversion from ‘long long unsigned int’ to ‘phys_addr_t’ {aka ‘unsigned int’} changes value from ‘4294967296’ to ‘0’ [-Woverflow]
 #define __AC(X,Y) (X##Y)
                   ^~~~~~
./include/uapi/linux/const.h:21:18: note: in expansion of macro ‘__AC’
 #define _AC(X,Y) __AC(X,Y)
                  ^~~~
./include/linux/sizes.h:46:18: note: in expansion of macro ‘_AC’
 #define SZ_4G    _AC(0x100000000, ULL)
                  ^~~
mm/cma.c:349:53: note: in expansion of macro ‘SZ_4G’
    addr = memblock_alloc_range_nid(size, alignment, SZ_4G,
                                                     ^~~~~