linux-kernel - Re: [PATCH v3 8/9] um: Fix -Wmissing-prototypes warnings for text

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Tue, 26 Mar 2024 23:05:48 +0800
From: "Tiwei Bie" <tiwei.btw@...group.com>
To: Lucas De Marchi <lucas.demarchi@...el.com>
Cc: richard@....at, anton.ivanov@...bridgegreys.com,
 johannes@...solutions.net, jani.nikula@...el.com,
 linux-um@...ts.infradead.org, linux-kernel@...r.kernel.org,
 intel-xe@...ts.freedesktop.org
Subject: Re: [PATCH v3 8/9] um: Fix -Wmissing-prototypes warnings for
 text_poke*

On 3/26/24 10:13 PM, Lucas De Marchi wrote:
> On Wed, Mar 06, 2024 at 06:19:24PM +0800, Tiwei Bie wrote:
>> The prototypes for text_poke* are declared in asm/text-patching.h
>> under arch/x86/include/. It's safe to include this header, as it's
>> UML-aware (by checking CONFIG_UML_X86).
> 
> but would it work when building on something other than x86? Or is that
> not a thing?

I think it doesn't matter, because uml is x86 only (i.e. uml only supports
x86 currently). And that's how uml works currently. I described the specific
header file to be included in the commit log just to make the changes easier
to review.

PS. The header is included via below search path set in arch/um/Makefile:

HEADER_ARCH     := $(SUBARCH)

ifneq ($(filter $(SUBARCH),x86 x86_64 i386),)
        HEADER_ARCH := x86 
endif
.....
HOST_DIR := arch/$(HEADER_ARCH)
.....
KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
                   -I$(srctree)/$(HOST_DIR)/include/uapi \
                   -I$(objtree)/$(HOST_DIR)/include/generated \
                   -I$(objtree)/$(HOST_DIR)/include/generated/uapi

Regards,
Tiwei

> 
> Lucas De Marchi
> 
>>
>> This will address below -Wmissing-prototypes warnings:
>>
>> arch/um/kernel/um_arch.c:461:7: warning: no previous prototype for ‘text_poke’ [-Wmissing-prototypes]
>> arch/um/kernel/um_arch.c:473:6: warning: no previous prototype for ‘text_poke_sync’ [-Wmissing-prototypes]
>>
>> Signed-off-by: Tiwei Bie <tiwei.btw@...group.com>
>> ---
>> arch/um/kernel/um_arch.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
>> index 7a9820797eae..e95f805e5004 100644
>> --- a/arch/um/kernel/um_arch.c
>> +++ b/arch/um/kernel/um_arch.c
>> @@ -23,6 +23,7 @@
>> #include <asm/cpufeature.h>
>> #include <asm/sections.h>
>> #include <asm/setup.h>
>> +#include <asm/text-patching.h>
>> #include <as-layout.h>
>> #include <arch.h>
>> #include <init.h>
>> -- 
>> 2.34.1
>>