[RFC PATCH] Rename ia32entry.S to entry_64_compat_32.S

[RFC PATCH] Rename ia32entry.S to entry_64_compat_32.S

[Ingo Molnar]

I'm wondering what people think about this naming scheme:

                  entry_32.S            # 32-bit binaries on 32-bit kernels
                  entry_64.S            # 64-bit binaries on 64-bit kernels
                  entry_64_compat_32.S  # 32-bit binaries on 64-bit kernels

Another option would be:

   arch/x86/entry/sys_32.S
   arch/x86/entry/sys_64.S
   arch/x86/entry/sys_64_compat.S

?

Thanks,

    Ingo
===

Ingo Molnar (1):
  x86/asm/entry/64/compat: Rename ia32entry.S -> entry_64_compat_32.S

 arch/x86/entry/Makefile                              | 2 +-
 arch/x86/entry/entry_64.S                            | 2 +-
 arch/x86/entry/{ia32entry.S => entry_64_compat_32.S} | 0
 3 files changed, 2 insertions(+), 2 deletions(-)
 rename arch/x86/entry/{ia32entry.S => entry_64_compat_32.S} (100%)

-- 
2.1.4

[PATCH] x86/asm/entry/64/compat: Rename ia32entry.S -> entry_64_compat_32.S

[Ingo Molnar]

So we now have the following system entry code related
files, which define the following system call instruction
and other entry paths:

   entry_32.S            # 32-bit binaries on 32-bit kernels
   entry_64.S            # 64-bit binaries on 64-bit kernels
   entry_64_compat_32.S  # 32-bit binaries on 64-bit kernels

Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/entry/Makefile                              | 2 +-
 arch/x86/entry/entry_64.S                            | 2 +-
 arch/x86/entry/{ia32entry.S => entry_64_compat_32.S} | 0
 3 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile
index b93cce1c6bb2..c1e6f5406f9e 100644
--- a/arch/x86/entry/Makefile
+++ b/arch/x86/entry/Makefile
@@ -6,5 +6,5 @@ obj-y				:= entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o
 obj-y				+= vdso/
 obj-y				+= vsyscall/
 
-obj-$(CONFIG_IA32_EMULATION)	+= ia32entry.o syscall_32.o
+obj-$(CONFIG_IA32_EMULATION)	+= entry_64_compat_32.o syscall_32.o
 
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 31770662b940..4cf3dd36aa0d 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -516,7 +516,7 @@ ENTRY(ret_from_fork)
 	/*
 	 * By the time we get here, we have no idea whether our pt_regs,
 	 * ti flags, and ti status came from the 64-bit SYSCALL fast path,
-	 * the slow path, or one of the ia32entry paths.
+	 * the slow path, or one of the 32-bit compat paths.
 	 * Use IRET code path to return, since it can safely handle
 	 * all of the above.
 	 */
diff --git a/arch/x86/entry/ia32entry.S b/arch/x86/entry/entry_64_compat_32.S
similarity index 100%
rename from arch/x86/entry/ia32entry.S
rename to arch/x86/entry/entry_64_compat_32.S
-- 
2.1.4

Re: [PATCH] x86/asm/entry/64/compat: Rename ia32entry.S -> entry_64_compat_32.S

[Brian Gerst]

On Fri, Jun 5, 2015 at 9:00 AM, Ingo Molnar <mingo@kernel.org> wrote:
> So we now have the following system entry code related
> files, which define the following system call instruction
> and other entry paths:
>
>    entry_32.S            # 32-bit binaries on 32-bit kernels
>    entry_64.S            # 64-bit binaries on 64-bit kernels
>    entry_64_compat_32.S  # 32-bit binaries on 64-bit kernels

That's too long.  How about just merging it into entry_64.S?  That
could also allow moving some of the obscure macros from calling.h into
entry_64.S where they are more visible.

--
Brian Gerst

Re: [RFC PATCH] Rename ia32entry.S to entry_64_compat_32.S

[Borislav Petkov]

On Fri, Jun 05, 2015 at 03:00:29PM +0200, Ingo Molnar wrote:
> I'm wondering what people think about this naming scheme:
> 
>                   entry_32.S            # 32-bit binaries on 32-bit kernels
>                   entry_64.S            # 64-bit binaries on 64-bit kernels
>                   entry_64_compat_32.S  # 32-bit binaries on 64-bit kernels
> 
> Another option would be:
> 
>    arch/x86/entry/sys_32.S
>    arch/x86/entry/sys_64.S
>    arch/x86/entry/sys_64_compat.S

I like this one better because entry_64_compat_32 kinda has both bitness in
there and confuses me more.

Just my 2 ¢. :)

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
--

Re: [RFC PATCH] Rename ia32entry.S to entry_64_compat_32.S

[H. Peter Anvin]

Call it sys if it is now only the system call entry points.  Agreed with _64_compat too.

Breaking up these snarls of spaghetti assembly will be a blessing.

On June 5, 2015 6:37:14 AM PDT, Borislav Petkov <bp@alien8.de> wrote:
>On Fri, Jun 05, 2015 at 03:00:29PM +0200, Ingo Molnar wrote:
>> I'm wondering what people think about this naming scheme:
>> 
>>                   entry_32.S            # 32-bit binaries on 32-bit
>kernels
>>                   entry_64.S            # 64-bit binaries on 64-bit
>kernels
>>                   entry_64_compat_32.S  # 32-bit binaries on 64-bit
>kernels
>> 
>> Another option would be:
>> 
>>    arch/x86/entry/sys_32.S
>>    arch/x86/entry/sys_64.S
>>    arch/x86/entry/sys_64_compat.S
>
>I like this one better because entry_64_compat_32 kinda has both
>bitness in
>there and confuses me more.
>
>Just my 2 ¢. :)

-- 
Sent from my mobile phone.  Please pardon brevity and lack of formatting.

Re: [RFC PATCH] Rename ia32entry.S to entry_64_compat_32.S

[Andy Lutomirski]

On Fri, Jun 5, 2015 at 2:09 PM, H. Peter Anvin <hpa@zytor.com> wrote:
> Call it sys if it is now only the system call entry points.  Agreed with _64_compat too.
>
> Breaking up these snarls of spaghetti assembly will be a blessing.

I'm not too picky about what we call it or whether we merge it with
entry_64.S.  *However*, I think the file name should end in _64.S.
The whole arch/x86 tree is arranged such that files that end in _64.S
or _64.c are build for 64-bit kernels and not for 32-bit kernels.  I
see no reason to deviate from that.

FWIW, I'm eventually planning to completely rewrite the compat entry
points to use the new (RFC patches coming in a week or two I hope!) C
exit code with opportunistic sysretl at the end.  I'm guessing the
result will be about half the size of the current code, and it'll be
comprehensible to mere mortals.

--Andy

>
> On June 5, 2015 6:37:14 AM PDT, Borislav Petkov <bp@alien8.de> wrote:
>>On Fri, Jun 05, 2015 at 03:00:29PM +0200, Ingo Molnar wrote:
>>> I'm wondering what people think about this naming scheme:
>>>
>>>                   entry_32.S            # 32-bit binaries on 32-bit
>>kernels
>>>                   entry_64.S            # 64-bit binaries on 64-bit
>>kernels
>>>                   entry_64_compat_32.S  # 32-bit binaries on 64-bit
>>kernels
>>>
>>> Another option would be:
>>>
>>>    arch/x86/entry/sys_32.S
>>>    arch/x86/entry/sys_64.S
>>>    arch/x86/entry/sys_64_compat.S
>>
>>I like this one better because entry_64_compat_32 kinda has both
>>bitness in
>>there and confuses me more.
>>
>>Just my 2 ¢. :)
>
> --
> Sent from my mobile phone.  Please pardon brevity and lack of formatting.



-- 
Andy Lutomirski
AMA Capital Management, LLC

Re: [RFC PATCH] Rename ia32entry.S to entry_64_compat_32.S

[Ingo Molnar]

* Andy Lutomirski <luto@amacapital.net> wrote:

> On Fri, Jun 5, 2015 at 2:09 PM, H. Peter Anvin <hpa@zytor.com> wrote:
> > Call it sys if it is now only the system call entry points.  Agreed with _64_compat too.
> >
> > Breaking up these snarls of spaghetti assembly will be a blessing.
> 
> I'm not too picky about what we call it or whether we merge it with entry_64.S.  
> *However*, I think the file name should end in _64.S. The whole arch/x86 tree is 
> arranged such that files that end in _64.S or _64.c are build for 64-bit kernels 
> and not for 32-bit kernels.  I see no reason to deviate from that.
> 
> FWIW, I'm eventually planning to completely rewrite the compat entry points to 
> use the new (RFC patches coming in a week or two I hope!) C exit code with 
> opportunistic sysretl at the end.  I'm guessing the result will be about half 
> the size of the current code, and it'll be comprehensible to mere mortals.

Ok, so I think the best is if I leave it alone for now: I've renamed it to 
entry_64_compat.S as per Boris's and hpa's suggestion, but won't merge it into 
entry_64.S (yet), let's see how your C conversion works out!

Thanks,

	Ingo