[PATCH 1/3] um: Adjust current_thread_info() for gcc-4.6

[PATCH 1/3] um: Adjust current_thread_info() for gcc-4.6

[Richard Weinberger]

In some cases gcc-4.6 will optimize away current_thread_info().
To prevent gcc from doing so the stack address has to be obtained
via inline asm.

LKML-Reference: http://marc.info/?i=201104132150.05623.richard@nod.at

Signed-off-by: Richard Weinberger <richard@nod.at>
---
 arch/um/include/asm/thread_info.h |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h
index e2cf786..5bd1bad 100644
--- a/arch/um/include/asm/thread_info.h
+++ b/arch/um/include/asm/thread_info.h
@@ -49,7 +49,10 @@ static inline struct thread_info *current_thread_info(void)
 {
 	struct thread_info *ti;
 	unsigned long mask = THREAD_SIZE - 1;
-	ti = (struct thread_info *) (((unsigned long) &ti) & ~mask);
+	void *p;
+
+	asm volatile ("" : "=r" (p) : "0" (&ti));
+	ti = (struct thread_info *) (((unsigned long)p) & ~mask);
 	return ti;
 }
 
-- 
1.7.4.2

[PATCH 3/3] uml: fix hppfs build

[Richard Weinberger]

From: Randy Dunlap <randy.dunlap@oracle.com>

Make HoneyPot ProcFS depend on CONFIG_PROC_FS so that it will build.
Recommended by Christoph Hellwig.

Fixes kernel bugzilla #33692:
  https://bugzilla.kernel.org/show_bug.cgi?id=33692

Reported-by: Simon Danner <danner.simon@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	Jeff Dike <jdike@addtoit.com>
Cc:	user-mode-linux-devel@lists.sourceforge.net
Cc:	Christoph Hellwig <hch@infradead.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
---
 arch/um/Kconfig.um |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/um/Kconfig.um b/arch/um/Kconfig.um
index 90a438a..b5e675e 100644
--- a/arch/um/Kconfig.um
+++ b/arch/um/Kconfig.um
@@ -47,7 +47,7 @@ config HOSTFS
 
 config HPPFS
 	tristate "HoneyPot ProcFS (EXPERIMENTAL)"
-	depends on EXPERIMENTAL
+	depends on EXPERIMENTAL && PROC_FS
 	help
 	  hppfs (HoneyPot ProcFS) is a filesystem which allows UML /proc
 	  entries to be overridden, removed, or fabricated from the host.
-- 
1.7.4.2

Re: [stable] [PATCH 2/3] um: Add support for 64 bit atomic operations

[Greg KH]

On Wed, Apr 20, 2011 at 01:34:25PM +0200, Richard Weinberger wrote:
> This adds support for 64 bit atomic operations on
> 32 bit UML systems.
> XFS needs them since 2.6.38.
> 
> Reported-by: Martin Walch <walch.martin@web.de>
> Tested-by: Martin Walch <walch.martin@web.de>
> Cc: Martin Walch <walch.martin@web.de>
> Cc: <stable@kernel.org> # .38.x 084189a: um: disable CONFIG_CMPXCHG_LOCAL

Why is this a stable patch?

confused,

greg k-h

Re: [stable] [PATCH 2/3] um: Add support for 64 bit atomic operations

[Richard Weinberger]

Am Mittwoch 20 April 2011, 16:27:02 schrieb Greg KH:
> On Wed, Apr 20, 2011 at 01:34:25PM +0200, Richard Weinberger wrote:
> > This adds support for 64 bit atomic operations on
> > 32 bit UML systems.
> > XFS needs them since 2.6.38.
> > 
> > Reported-by: Martin Walch <walch.martin@web.de>
> > Tested-by: Martin Walch <walch.martin@web.de>
> > Cc: Martin Walch <walch.martin@web.de>
> > Cc: <stable@kernel.org> # .38.x 084189a: um: disable CONFIG_CMPXCHG_LOCAL
> 
> Why is this a stable patch?

Because it fixes a build error in 2.6.38.
See: https://bugzilla.kernel.org/show_bug.cgi?id=32812

Thanks,
//richard

> confused,
> 
> greg k-h

Re: [stable] [PATCH 2/3] um: Add support for 64 bit atomic operations

[Greg KH]

On Wed, Apr 20, 2011 at 04:29:23PM +0200, Richard Weinberger wrote:
> Am Mittwoch 20 April 2011, 16:27:02 schrieb Greg KH:
> > On Wed, Apr 20, 2011 at 01:34:25PM +0200, Richard Weinberger wrote:
> > > This adds support for 64 bit atomic operations on
> > > 32 bit UML systems.
> > > XFS needs them since 2.6.38.
> > > 
> > > Reported-by: Martin Walch <walch.martin@web.de>
> > > Tested-by: Martin Walch <walch.martin@web.de>
> > > Cc: Martin Walch <walch.martin@web.de>
> > > Cc: <stable@kernel.org> # .38.x 084189a: um: disable CONFIG_CMPXCHG_LOCAL
> > 
> > Why is this a stable patch?
> 
> Because it fixes a build error in 2.6.38.
> See: https://bugzilla.kernel.org/show_bug.cgi?id=32812

Then why not put that in the changelog entry in the first place?

thanks,

greg "please save me time" k-h

Re: [stable] [PATCH 2/3] um: Add support for 64 bit atomic operations

[Richard Weinberger]

Am Mittwoch 20 April 2011, 16:34:08 schrieb Greg KH:
> On Wed, Apr 20, 2011 at 04:29:23PM +0200, Richard Weinberger wrote:
> > Am Mittwoch 20 April 2011, 16:27:02 schrieb Greg KH:
> > > On Wed, Apr 20, 2011 at 01:34:25PM +0200, Richard Weinberger wrote:
> > > > This adds support for 64 bit atomic operations on
> > > > 32 bit UML systems.
> > > > XFS needs them since 2.6.38.
> > > > 
> > > > Reported-by: Martin Walch <walch.martin@web.de>
> > > > Tested-by: Martin Walch <walch.martin@web.de>
> > > > Cc: Martin Walch <walch.martin@web.de>
> > > > Cc: <stable@kernel.org> # .38.x 084189a: um: disable
> > > > CONFIG_CMPXCHG_LOCAL
> > > 
> > > Why is this a stable patch?
> > 
> > Because it fixes a build error in 2.6.38.
> > See: https://bugzilla.kernel.org/show_bug.cgi?id=32812
> 
> Then why not put that in the changelog entry in the first place?

Sorry, will do better next time!

Thanks,
//richard

> thanks,
> 
> greg "please save me time" k-h