On Wed, Jul 04, 2018 at 02:36:27PM +0200, Michal Hocko wrote:
[CC Andrew - email thread starts http://lkml.kernel.org/r/1530685696-14672-1-git-send-email-rppt@xxxxxxxxxxxxxxxxxx] OK, so here we go with the full patch. From 0e8432b875d98a7a0d3f757fce2caa8d16a8de15 Mon Sep 17 00:00:00 2001 From: Michal Hocko <mhocko@xxxxxxxx> Date: Wed, 4 Jul 2018 14:31:46 +0200 Subject: [PATCH] memblock: do not complain about top-down allocations for !MEMORY_HOTREMOVE Mike Rapoport is converting architectures from bootmem to noboodmem allocator. While doing so for m68k Geert has noticed that he gets a scary looking warning WARNING: CPU: 0 PID: 0 at mm/memblock.c:230 memblock_find_in_range_node+0x11c/0x1be memblock: bottom-up allocation failed, memory hotunplug may be affected Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 4.18.0-rc3-atari-01343-gf2fb5f2e09a97a3c-dirty #7 Stack from 003c3e20: 003c3e20 0039cf44 00023800 00433000 ffffffff 00001000 00240000 000238aa 00378734 000000e6 004285ac 00000009 00000000 003c3e58 003787c0 003c3e74 003c3ea4 004285ac 00378734 000000e6 003787c0 00000000 00000000 00000001 00000000 00000010 00000000 00428490 003e3856 ffffffff ffffffff 003c3ed0 00044620 003c3ee0 00417a10 00240000 00000010 00000000 00000000 00000001 00000000 00000001 00240000 00000000 00000000 00000000 00001000 003e3856 Call Trace: [<00023800>] __warn+0xa8/0xc2 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00240000>] netdev_lower_get_next+0x2/0x22 [<000238aa>] warn_slowpath_fmt+0x2e/0x36 [<004285ac>] memblock_find_in_range_node+0x11c/0x1be [<004285ac>] memblock_find_in_range_node+0x11c/0x1be [<00428490>] memblock_find_in_range_node+0x0/0x1be [<00044620>] vprintk_func+0x66/0x6e [<00417a10>] memblock_virt_alloc_internal+0xd0/0x156 [<00240000>] netdev_lower_get_next+0x2/0x22 [<00240000>] netdev_lower_get_next+0x2/0x22 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00417b8c>] memblock_virt_alloc_try_nid_nopanic+0x58/0x7a [<00240000>] netdev_lower_get_next+0x2/0x22 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00010000>] EXPTBL+0x234/0x400 [<00010000>] EXPTBL+0x234/0x400 [<002f3644>] alloc_node_mem_map+0x4a/0x66 [<00240000>] netdev_lower_get_next+0x2/0x22 [<004155ca>] free_area_init_node+0xe2/0x29e [<00010000>] EXPTBL+0x234/0x400 [<00411392>] paging_init+0x430/0x462 [<00001000>] kernel_pg_dir+0x0/0x1000 [<000427cc>] printk+0x0/0x1a [<00010000>] EXPTBL+0x234/0x400 [<0041084c>] setup_arch+0x1b8/0x22c [<0040e020>] start_kernel+0x4a/0x40a [<0040d344>] _sinittext+0x344/0x9e8 The warning is basically saying that a top-down allocation can break memory hotremove because memblock allocation is not movable. But m68k doesn't even support MEMORY_HOTREMOVE is there is no point to warn about it. Make the warning conditional only to configurations that care. Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Tested-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> --- mm/memblock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/memblock.c b/mm/memblock.c index 03d48d8835ba..2acec4033389 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -227,7 +227,8 @@ phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size, * so we use WARN_ONCE() here to see the stack trace if * fail happens. */ - WARN_ONCE(1, "memblock: bottom-up allocation failed, memory hotunplug may be affected\n"); + WARN_ONCE(IS_ENABLED(CONFIG_MEMORY_HOTREMOVE), + "memblock: bottom-up allocation failed, memory hotremove may be affected\n");
nit: isn't the warning indented too much?
} return __memblock_find_range_top_down(start, end, size, align, nid, -- 2.18.0 -- Michal Hocko SUSE Labs
-- Sincerely yours, Mike. -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
