Re: [Xen-devel] [PATCH] rombios: work around clang's -Waddress-of-packed-member

2018-08-27 Thread Jan Beulich 
>>> On 24.08.18 at 17:22,  wrote:
> Building rombios with clang XXX fails with:
> 
> tcgbios.c:1519:34: error: taking address of packed member 'u' of class or 
> structure 'pushad_regs_t' may result in an unaligned pointer value 
> [-Werror,-Waddress-of-packed-member]
>   ®s->u.r32.edx);
>^~~
> 
> Work around that by using an intermediate variable.
> 
> Signed-off-by: Wei Liu 
> ---
>  tools/firmware/rombios/32bit/tcgbios/tcgbios.c | 7 +--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/firmware/rombios/32bit/tcgbios/tcgbios.c 
> b/tools/firmware/rombios/32bit/tcgbios/tcgbios.c
> index fa22c4460a..581340da8e 100644
> --- a/tools/firmware/rombios/32bit/tcgbios/tcgbios.c
> +++ b/tools/firmware/rombios/32bit/tcgbios/tcgbios.c
> @@ -1507,7 +1507,8 @@ uint32_t TCGInterruptHandler(pushad_regs_t *regs, 
> uint32_t esds,
> regs->u.r32.edx);
>   CLEAR_CF();
>   break;
> - case 0x07:
> + case 0x07: {
> + uint32_t edx = regs->u.r32.edx;
>   regs->u.r32.eax =
> CompactHashLogExtendEvent32((unsigned char *)
> ADDR_FROM_SEG_OFF(ES,
> @@ -1516,9 +1517,11 @@ uint32_t TCGInterruptHandler(pushad_regs_t *regs, 
> uint32_t esds,
> regs->u.r32.ebx,
> regs->u.r32.ecx,
> regs->u.r32.edx,
> -   >u.r32.edx);
> +   );
> + regs->u.r32.edx = edx;
>   CLEAR_CF();
>   break;
> + }

Hmm, this addresses a specific instance of the problem. In this (I think)
never changing code base doing so might be okay, but is there a reason
not to fix the root of the problem - remove the bogus packed attribute?
The structure definition in 32bit/rombios_compat.h spells out all padding
fields, and I can't spot any other (side) effect the attribute would have,
the more that it's only the outermost structure which gets the attribute
applied.

Jan


___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

Re: [Xen-devel] [PATCH] rombios: work around clang's -Waddress-of-packed-member

2018-08-24 Thread Wei Liu 
On Fri, Aug 24, 2018 at 04:32:15PM +0100, Wei Liu wrote:
> On Fri, Aug 24, 2018 at 10:30:37AM -0500, Doug Goldstein wrote:
> > On Fri, Aug 24, 2018 at 04:22:15PM +0100, Wei Liu wrote:
> > > Building rombios with clang XXX fails with:
> 
> Oops, I have meant to replace XXX with the right version number.
> 
> Will fix that while committing.

The version used in Debian unstable is 6.0.1-2 (tags/RELEASE_601/final)

Wei.

___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

Re: [Xen-devel] [PATCH] rombios: work around clang's -Waddress-of-packed-member

2018-08-24 Thread Wei Liu 
On Fri, Aug 24, 2018 at 10:30:37AM -0500, Doug Goldstein wrote:
> On Fri, Aug 24, 2018 at 04:22:15PM +0100, Wei Liu wrote:
> > Building rombios with clang XXX fails with:

Oops, I have meant to replace XXX with the right version number.

Will fix that while committing.

> > 
> > tcgbios.c:1519:34: error: taking address of packed member 'u' of class or 
> > structure 'pushad_regs_t' may result in an unaligned pointer value 
> > [-Werror,-Waddress-of-packed-member]
> >   ®s->u.r32.edx);
> >^~~
> > 
> > Work around that by using an intermediate variable.
> > 
> > Signed-off-by: Wei Liu 
> 
> Reviewed-by: Doug Goldstein 

___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

Re: [Xen-devel] [PATCH] rombios: work around clang's -Waddress-of-packed-member

2018-08-24 Thread Doug Goldstein 
On Fri, Aug 24, 2018 at 04:22:15PM +0100, Wei Liu wrote:
> Building rombios with clang XXX fails with:
> 
> tcgbios.c:1519:34: error: taking address of packed member 'u' of class or 
> structure 'pushad_regs_t' may result in an unaligned pointer value 
> [-Werror,-Waddress-of-packed-member]
>   ®s->u.r32.edx);
>^~~
> 
> Work around that by using an intermediate variable.
> 
> Signed-off-by: Wei Liu 

Reviewed-by: Doug Goldstein 

___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

[Xen-devel] [PATCH] rombios: work around clang's -Waddress-of-packed-member

2018-08-24 Thread Wei Liu 
Building rombios with clang XXX fails with:

tcgbios.c:1519:34: error: taking address of packed member 'u' of class or 
structure 'pushad_regs_t' may result in an unaligned pointer value 
[-Werror,-Waddress-of-packed-member]
  ®s->u.r32.edx);
   ^~~

Work around that by using an intermediate variable.

Signed-off-by: Wei Liu 
---
 tools/firmware/rombios/32bit/tcgbios/tcgbios.c | 7 +--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/firmware/rombios/32bit/tcgbios/tcgbios.c 
b/tools/firmware/rombios/32bit/tcgbios/tcgbios.c
index fa22c4460a..581340da8e 100644
--- a/tools/firmware/rombios/32bit/tcgbios/tcgbios.c
+++ b/tools/firmware/rombios/32bit/tcgbios/tcgbios.c
@@ -1507,7 +1507,8 @@ uint32_t TCGInterruptHandler(pushad_regs_t *regs, 
uint32_t esds,
  regs->u.r32.edx);
CLEAR_CF();
break;
-   case 0x07:
+   case 0x07: {
+   uint32_t edx = regs->u.r32.edx;
regs->u.r32.eax =
  CompactHashLogExtendEvent32((unsigned char *)
  ADDR_FROM_SEG_OFF(ES,
@@ -1516,9 +1517,11 @@ uint32_t TCGInterruptHandler(pushad_regs_t *regs, 
uint32_t esds,
  regs->u.r32.ebx,
  regs->u.r32.ecx,
  regs->u.r32.edx,
- >u.r32.edx);
+ );
+   regs->u.r32.edx = edx;
CLEAR_CF();
break;
+   }
default:
SET_CF();
}
-- 
2.11.0


___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel