| Message ID | 1465483016-27311-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c index ef7d6c8..f354fd8 100644 --- a/arch/s390/mm/vmem.c +++ b/arch/s390/mm/vmem.c @@ -372,7 +372,7 @@ void __init vmem_map_init(void) ro_end = (unsigned long)&_eshared & PAGE_MASK; for_each_memblock(memory, reg) { start = reg->base; - end = reg->base + reg->size - 1; + end = reg->base + reg->size; if (start >= ro_end || end <= ro_start) vmem_add_mem(start, end - start, 0); else if (start >= ro_start && end <= ro_end)
This is a note to let you know that I have just added a patch titled s390/vmem: fix identity mapping to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree which can be found at: https://git.launchpad.net/~canonical-kernel/linux/+git/linux-stable-ckt/log/?h=linux-4.2.y-queue This patch is scheduled to be released in version 4.2.8-ckt12. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 4.2.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 957cf52e2eb519a0d3427341da09e79c0a148548 Mon Sep 17 00:00:00 2001 From: Heiko Carstens <heiko.carstens@de.ibm.com> Date: Tue, 10 May 2016 12:10:22 +0200 Subject: s390/vmem: fix identity mapping commit c34a69059d7876e0793eb410deedfb08ccb22b02 upstream. The identity mapping is suboptimal for the last 2GB frame. The mapping will be established with a mix of 4KB and 1MB mappings instead of a single 2GB mapping. This happens because of a off-by-one bug introduced with commit 50be63450728 ("s390/mm: Convert bootmem to memblock"). Currently the identity mapping looks like this: 0x0000000080000000-0x0000000180000000 4G PUD RW 0x0000000180000000-0x00000001fff00000 2047M PMD RW 0x00000001fff00000-0x0000000200000000 1M PTE RW With the bug fixed it looks like this: 0x0000000080000000-0x0000000200000000 6G PUD RW Fixes: 50be63450728 ("s390/mm: Convert bootmem to memblock") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- arch/s390/mm/vmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.7.4