xtensa: fix high memory/reserved memory collision
Xtensa memory initialization code frees high memory pages without
checking whether they are in the reserved memory regions or not. That
results in invalid value of totalram_pages and duplicate page usage by
CMA and highmem. It produces a bunch of BUGs at startup looking like
this:
BUG: Bad page state in process swapper pfn:70800
page:be60c000 count:0 mapcount:-127 mapping: (null) index:0x1
flags: 0x80000000()
raw: 80000000 00000000 00000001 ffffff80 00000000 be60c014 be60c014 0000000a
page dumped because: nonzero mapcount
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Tainted: G B 4.16.0-rc1-00015-g7928b2cbe55b-dirty #23
Stack:
bd839d33 00000000 00000018 ba97b64c a106578c bd839d70 be60c000 00000000
a1378054 bd86a000 00000003 ba97b64c a1066166 bd839da0 be60c000 ffe00000
a1066b58 bd839dc0 be504000 00000000 000002f4 bd838000 00000000 0000001e
Call Trace:
[<a1065734>] bad_page+0xac/0xd0
[<a106578c>] free_pages_check_bad+0x34/0x4c
[<a1066166>] __free_pages_ok+0xae/0x14c
[<a1066b58>] __free_pages+0x30/0x64
[<a1365de5>] init_cma_reserved_pageblock+0x35/0x44
[<a13682dc>] cma_init_reserved_areas+0xf4/0x148
[<a10034b8>] do_one_initcall+0x80/0xf8
[<a1361c16>] kernel_init_freeable+0xda/0x13c
[<a125b59d>] kernel_init+0x9/0xd0
[<a1004304>] ret_from_kernel_thread+0xc/0x18
Only free high memory pages that are not reserved.
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
1 file changed