* [PATCH] MIPS: Fix unable to reserve memory for Crash kernel
@ 2020-07-25 5:56 Jinyang He
2020-07-25 7:01 ` Jiaxun Yang
2020-07-26 11:57 ` Thomas Bogendoerfer
0 siblings, 2 replies; 3+ messages in thread
From: Jinyang He @ 2020-07-25 5:56 UTC (permalink / raw)
To: linux-mips; +Cc: Jinyang He
Use 0 as the align parameter in memblock_find_in_range() is
incorrect when we reserve memory for Crash kernel.
The environment as follows:
[ 0.000000] MIPS: machine is loongson,loongson64c-4core-rs780e
...
[ 1.951016] crashkernel=64M@128M
The warning as follows:
[ 0.000000] Invalid memory region reserved for crash kernel
And the iomem as follows:
00200000-0effffff : System RAM
04000000-0484009f : Kernel code
048400a0-04ad7fff : Kernel data
04b40000-05c4c6bf : Kernel bss
1a000000-1bffffff : pci@1a000000
...
The align parameter may be finally used by round_down() or round_up().
Like the following call tree:
mips-next: mm/memblock.c
memblock_find_in_range
└── memblock_find_in_range_node
├── __memblock_find_range_bottom_up
│ └── round_up
└── __memblock_find_range_top_down
└── round_down
\#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
\#define round_down(x, y) ((x) & ~__round_mask(x, y))
\#define __round_mask(x, y) ((__typeof__(x))((y)-1))
The round_down(or round_up)'s second parameter must be a power of 2.
If the second parameter is 0, it both will return 0.
Use 1 as the parameter to fix the bug and the iomem as follows:
00200000-0effffff : System RAM
04000000-0484009f : Kernel code
048400a0-04ad7fff : Kernel data
04b40000-05c4c6bf : Kernel bss
08000000-0bffffff : Crash kernel
1a000000-1bffffff : pci@1a000000
...
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
---
arch/mips/kernel/setup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 7b537fa..588b212 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -497,7 +497,7 @@ static void __init mips_parse_crashkernel(void)
if (ret != 0 || crash_size <= 0)
return;
- if (!memblock_find_in_range(crash_base, crash_base + crash_size, crash_size, 0)) {
+ if (!memblock_find_in_range(crash_base, crash_base + crash_size, crash_size, 1)) {
pr_warn("Invalid memory region reserved for crash kernel\n");
return;
}
--
2.1.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] MIPS: Fix unable to reserve memory for Crash kernel
2020-07-25 5:56 [PATCH] MIPS: Fix unable to reserve memory for Crash kernel Jinyang He
@ 2020-07-25 7:01 ` Jiaxun Yang
2020-07-26 11:57 ` Thomas Bogendoerfer
1 sibling, 0 replies; 3+ messages in thread
From: Jiaxun Yang @ 2020-07-25 7:01 UTC (permalink / raw)
To: Jinyang He, linux-mips
在 2020/7/25 13:56, Jinyang He 写道:
> Use 0 as the align parameter in memblock_find_in_range() is
> incorrect when we reserve memory for Crash kernel.
>
> The environment as follows:
> [ 0.000000] MIPS: machine is loongson,loongson64c-4core-rs780e
> ...
> [ 1.951016] crashkernel=64M@128M
>
> The warning as follows:
> [ 0.000000] Invalid memory region reserved for crash kernel
>
> And the iomem as follows:
> 00200000-0effffff : System RAM
> 04000000-0484009f : Kernel code
> 048400a0-04ad7fff : Kernel data
> 04b40000-05c4c6bf : Kernel bss
> 1a000000-1bffffff : pci@1a000000
> ...
>
> The align parameter may be finally used by round_down() or round_up().
> Like the following call tree:
>
> mips-next: mm/memblock.c
>
> memblock_find_in_range
> └── memblock_find_in_range_node
> ├── __memblock_find_range_bottom_up
> │ └── round_up
> └── __memblock_find_range_top_down
> └── round_down
> \#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
> \#define round_down(x, y) ((x) & ~__round_mask(x, y))
> \#define __round_mask(x, y) ((__typeof__(x))((y)-1))
>
> The round_down(or round_up)'s second parameter must be a power of 2.
> If the second parameter is 0, it both will return 0.
>
> Use 1 as the parameter to fix the bug and the iomem as follows:
> 00200000-0effffff : System RAM
> 04000000-0484009f : Kernel code
> 048400a0-04ad7fff : Kernel data
> 04b40000-05c4c6bf : Kernel bss
> 08000000-0bffffff : Crash kernel
> 1a000000-1bffffff : pci@1a000000
> ...
>
> Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Oops, looks like my fault during switch boot_mem_map to memblock.
Thanks.
- Jiaxun
> ---
> arch/mips/kernel/setup.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
> index 7b537fa..588b212 100644
> --- a/arch/mips/kernel/setup.c
> +++ b/arch/mips/kernel/setup.c
> @@ -497,7 +497,7 @@ static void __init mips_parse_crashkernel(void)
> if (ret != 0 || crash_size <= 0)
> return;
>
> - if (!memblock_find_in_range(crash_base, crash_base + crash_size, crash_size, 0)) {
> + if (!memblock_find_in_range(crash_base, crash_base + crash_size, crash_size, 1)) {
> pr_warn("Invalid memory region reserved for crash kernel\n");
> return;
> }
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] MIPS: Fix unable to reserve memory for Crash kernel
2020-07-25 5:56 [PATCH] MIPS: Fix unable to reserve memory for Crash kernel Jinyang He
2020-07-25 7:01 ` Jiaxun Yang
@ 2020-07-26 11:57 ` Thomas Bogendoerfer
1 sibling, 0 replies; 3+ messages in thread
From: Thomas Bogendoerfer @ 2020-07-26 11:57 UTC (permalink / raw)
To: Jinyang He; +Cc: linux-mips
On Sat, Jul 25, 2020 at 01:56:38PM +0800, Jinyang He wrote:
> Use 0 as the align parameter in memblock_find_in_range() is
> incorrect when we reserve memory for Crash kernel.
>
> The environment as follows:
> [ 0.000000] MIPS: machine is loongson,loongson64c-4core-rs780e
> ...
> [ 1.951016] crashkernel=64M@128M
>
> The warning as follows:
> [ 0.000000] Invalid memory region reserved for crash kernel
>
> And the iomem as follows:
> 00200000-0effffff : System RAM
> 04000000-0484009f : Kernel code
> 048400a0-04ad7fff : Kernel data
> 04b40000-05c4c6bf : Kernel bss
> 1a000000-1bffffff : pci@1a000000
> ...
>
> The align parameter may be finally used by round_down() or round_up().
> Like the following call tree:
>
> mips-next: mm/memblock.c
>
> memblock_find_in_range
> └── memblock_find_in_range_node
> ├── __memblock_find_range_bottom_up
> │ └── round_up
> └── __memblock_find_range_top_down
> └── round_down
> \#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
> \#define round_down(x, y) ((x) & ~__round_mask(x, y))
> \#define __round_mask(x, y) ((__typeof__(x))((y)-1))
>
> The round_down(or round_up)'s second parameter must be a power of 2.
> If the second parameter is 0, it both will return 0.
>
> Use 1 as the parameter to fix the bug and the iomem as follows:
> 00200000-0effffff : System RAM
> 04000000-0484009f : Kernel code
> 048400a0-04ad7fff : Kernel data
> 04b40000-05c4c6bf : Kernel bss
> 08000000-0bffffff : Crash kernel
> 1a000000-1bffffff : pci@1a000000
> ...
>
> Signed-off-by: Jinyang He <hejinyang@loongson.cn>
> ---
> arch/mips/kernel/setup.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
applied to mips-next.
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
^ permalink raw reply [flat|nested] 3+ messages in thread
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2020-07-25 5:56 [PATCH] MIPS: Fix unable to reserve memory for Crash kernel Jinyang He
2020-07-25 7:01 ` Jiaxun Yang
2020-07-26 11:57 ` Thomas Bogendoerfer
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