[PATCH fixes 1/3] MIPS: Loongson64: Reserve vgabios memory on boot

Jiaxun Yang posted 3 patches 2 years, 1 month ago
There is a newer version of this series
[PATCH fixes 1/3] MIPS: Loongson64: Reserve vgabios memory on boot
Posted by Jiaxun Yang 2 years, 1 month ago
vgabios is passed from firmware to kernel on Loongson64 systems.
Sane firmware will keep this pointer in reserved memory space
passed from the firmware but insane firmware keeps it in low
memory before kernel entry that is not reserved.

Previously kernel won't try to allocate memory from low memory
before kernel entry on boot, but after converting to memblock
it will do that.

Fix by resversing those memory on early boot.

Cc: stable@vger.kernel.org
Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---
 arch/mips/loongson64/init.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/mips/loongson64/init.c b/arch/mips/loongson64/init.c
index ee8de1735b7c..d62262f93069 100644
--- a/arch/mips/loongson64/init.c
+++ b/arch/mips/loongson64/init.c
@@ -88,6 +88,11 @@ void __init szmem(unsigned int node)
 			break;
 		}
 	}
+
+	/* Reserve vgabios if it comes from firmware */
+	if (loongson_sysconf.vgabios_addr)
+		memblock_reserve(virt_to_phys((void *)loongson_sysconf.vgabios_addr),
+				SZ_256K);
 }
 
 #ifndef CONFIG_NUMA

-- 
2.34.1
Re: [PATCH fixes 1/3] MIPS: Loongson64: Reserve vgabios memory on boot
Posted by Sergey Shtylyov 2 years, 1 month ago
On 11/1/23 2:39 PM, Jiaxun Yang wrote:

> vgabios is passed from firmware to kernel on Loongson64 systems.
> Sane firmware will keep this pointer in reserved memory space
> passed from the firmware but insane firmware keeps it in low
> memory before kernel entry that is not reserved.
> 
> Previously kernel won't try to allocate memory from low memory
> before kernel entry on boot, but after converting to memblock
> it will do that.
> 
> Fix by resversing those memory on early boot.

   Reserving? :-)

> Cc: stable@vger.kernel.org
> Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
[...]

MBR, Sergey