* [PATCH] ARC: adjust memblock_reserve of kernel memory
@ 2018-12-19 16:16 Eugeniy Paltsev
2018-12-20 3:49 ` Vineet Gupta
2018-12-20 4:00 ` Vineet Gupta
0 siblings, 2 replies; 3+ messages in thread
From: Eugeniy Paltsev @ 2018-12-19 16:16 UTC (permalink / raw)
To: linux-snps-arc, Vineet Gupta
Cc: linux-kernel, Alexey Brodkin, stable, Eugeniy Paltsev
In setup_arch_memory we reserve the memory area wherein the kernel
is located. Current implementation may reserve more memory than
it actually required in case of CONFIG_LINUX_LINK_BASE is not
equal to CONFIG_LINUX_RAM_BASE. This happens because we calculate
start of the reserved region relatively to the CONFIG_LINUX_RAM_BASE
and end of the region relatively to the CONFIG_LINUX_RAM_BASE.
For example in case of HSDK board we wasted 256MiB of physical memory:
------------------->8------------------------------
Memory: 770416K/1048576K available (5496K kernel code,
240K rwdata, 1064K rodata, 2200K init, 275K bss,
278160K reserved, 0K cma-reserved)
------------------->8------------------------------
Fix that.
Cc: stable@vger.kernel.org
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
arch/arc/mm/init.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index f8fe5668b30f..a56e6a8ed259 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -137,7 +137,8 @@ void __init setup_arch_memory(void)
*/
memblock_add_node(low_mem_start, low_mem_sz, 0);
- memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);
+ memblock_reserve(CONFIG_LINUX_LINK_BASE,
+ __pa(_end) - CONFIG_LINUX_LINK_BASE);
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_start)
--
2.14.5
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] ARC: adjust memblock_reserve of kernel memory
2018-12-19 16:16 [PATCH] ARC: adjust memblock_reserve of kernel memory Eugeniy Paltsev
@ 2018-12-20 3:49 ` Vineet Gupta
2018-12-20 4:00 ` Vineet Gupta
1 sibling, 0 replies; 3+ messages in thread
From: Vineet Gupta @ 2018-12-20 3:49 UTC (permalink / raw)
To: Eugeniy Paltsev, linux-snps-arc; +Cc: linux-kernel, Alexey Brodkin, stable
On 12/19/18 8:16 AM, Eugeniy Paltsev wrote:
> In setup_arch_memory we reserve the memory area wherein the kernel
> is located. Current implementation may reserve more memory than
> it actually required in case of CONFIG_LINUX_LINK_BASE is not
> equal to CONFIG_LINUX_RAM_BASE. This happens because we calculate
> start of the reserved region relatively to the CONFIG_LINUX_RAM_BASE
> and end of the region relatively to the CONFIG_LINUX_RAM_BASE.
>
> For example in case of HSDK board we wasted 256MiB of physical memory:
> ------------------->8------------------------------
> Memory: 770416K/1048576K available (5496K kernel code,
> 240K rwdata, 1064K rodata, 2200K init, 275K bss,
> 278160K reserved, 0K cma-reserved)
> ------------------->8------------------------------
>
> Fix that.
>
> Cc: stable@vger.kernel.org
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
LGTM. I presume you have booted HSDK with it and done some smoke testing.
-Vineet
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] ARC: adjust memblock_reserve of kernel memory
2018-12-19 16:16 [PATCH] ARC: adjust memblock_reserve of kernel memory Eugeniy Paltsev
2018-12-20 3:49 ` Vineet Gupta
@ 2018-12-20 4:00 ` Vineet Gupta
1 sibling, 0 replies; 3+ messages in thread
From: Vineet Gupta @ 2018-12-20 4:00 UTC (permalink / raw)
To: Eugeniy Paltsev, linux-snps-arc; +Cc: linux-kernel, Alexey Brodkin, stable
On 12/19/18 8:16 AM, Eugeniy Paltsev wrote:
> In setup_arch_memory we reserve the memory area wherein the kernel
> is located. Current implementation may reserve more memory than
> it actually required in case of CONFIG_LINUX_LINK_BASE is not
> equal to CONFIG_LINUX_RAM_BASE. This happens because we calculate
> start of the reserved region relatively to the CONFIG_LINUX_RAM_BASE
> and end of the region relatively to the CONFIG_LINUX_RAM_BASE.
>
> For example in case of HSDK board we wasted 256MiB of physical memory:
> ------------------->8------------------------------
> Memory: 770416K/1048576K available (5496K kernel code,
> 240K rwdata, 1064K rodata, 2200K init, 275K bss,
> 278160K reserved, 0K cma-reserved)
> ------------------->8------------------------------
>
> Fix that.
>
> Cc: stable@vger.kernel.org
For backports, please also check how far back this needs to be applied (else we
get bot emails specifying they don't apply to ver x, y z)
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
> ---
> arch/arc/mm/init.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
> index f8fe5668b30f..a56e6a8ed259 100644
> --- a/arch/arc/mm/init.c
> +++ b/arch/arc/mm/init.c
> @@ -137,7 +137,8 @@ void __init setup_arch_memory(void)
> */
>
> memblock_add_node(low_mem_start, low_mem_sz, 0);
> - memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);
> + memblock_reserve(CONFIG_LINUX_LINK_BASE,
> + __pa(_end) - CONFIG_LINUX_LINK_BASE);
>
> #ifdef CONFIG_BLK_DEV_INITRD
> if (initrd_start)
So I looked into the history for restricting stable, and it seems this was
introduced with our earlier work for HSDK.
Before commit 9ed68785f7f this code was ok, since low_mem_start =
CONFIG_LINUX_LINK_BASE.
With the patch we changed low_mem_start to CONFIG_LINUX_RAM_BASE and missed this.
-Vineet
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2018-12-20 4:00 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-12-19 16:16 [PATCH] ARC: adjust memblock_reserve of kernel memory Eugeniy Paltsev
2018-12-20 3:49 ` Vineet Gupta
2018-12-20 4:00 ` Vineet Gupta
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).