lkml.org 
[lkml]   [2019]   [Feb]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] x86/boot: Move detecting acpi=off in cmdline to get_rsdp_addr()
On Fri, Feb 15, 2019 at 10:28:41AM +0100, Borislav Petkov wrote:
>On Fri, Feb 15, 2019 at 05:10:47PM +0800, Chao Fan wrote:
>> If "acpi=off" specified in cmdline, the whole functions of acpi.c
>> should not work, there is no need to ealy parse RSDP, so detect
>> "acpi=off" in the very first place.
>>
>> Also replace magic number with macro.
>>
>> Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
>> ---
>> arch/x86/boot/compressed/acpi.c | 12 ++++++------
>> 1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
>> index 0ef4ad55b29b..5510a2105b7b 100644
>> --- a/arch/x86/boot/compressed/acpi.c
>> +++ b/arch/x86/boot/compressed/acpi.c
>> @@ -213,8 +213,13 @@ static acpi_physical_address bios_get_rsdp_addr(void)
>> /* Return RSDP address on success, otherwise 0. */
>> acpi_physical_address get_rsdp_addr(void)
>> {
>> + char arg[MAX_ACPI_ARG_LENGTH];
>> acpi_physical_address pa;
>>
>> + if (cmdline_find_option("acpi", arg, sizeof(arg)) == 3 &&
>> + !strncmp(arg, "off", 3))
>> + return 0;
>
>This place looks wrong because we have a get_acpi_rsdp() call before
>that which overrides acpi=off practically.

Oh thanks.
In my old version PATCH, it was in count_immovable_mem_regions() which
is the entry function of acpi.c. Then in last version, I splite acpi.c
so that the first entry is get_rsdp_addr(), that's why I want to move
the detecting here.

>
>Also, if you move it to get_rsdp_addr(), add a static variable recording
>the previous result of the cmdline parsing because I don't want it
>parsing cmdline each time it is called.

Thanks,
Chao Fan

>
>Thx.
>
>--
>Regards/Gruss,
> Boris.
>
>Good mailing practices for 400: avoid top-posting and trim the reply.
>
>


\
 
 \ /
  Last update: 2019-02-15 10:47    [W:0.036 / U:4.764 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site