2.6.22-rc7: known regressions with patches

2.6.22-rc7: known regressions with patches

[Michal Piotrowski]

Hi all,

Here is a list of some known regressions in 2.6.22-rc7
with patches available.

Feel free to add new regressions/remove fixed etc.
http://kernelnewbies.org/known_regressions

List of Aces

Name                    Regressions fixed since 21-Jun-2007
Hugh Dickins                           2
Andi Kleen                             1
Andrew Morton                          1
Benjamin Herrenschmidt                 1
Björn Steinbrink                       1
Bjorn Helgaas                          1
Jean Delvare                           1
Olaf Hering                            1
Siddha, Suresh B                       1
Trent Piepho                           1
Ville Syrjälä                          1



Unclassified

Subject         : inconsistent lock state
References      : http://lkml.org/lkml/2007/7/3/195
Last known good : ?
Submitter       : Andre Noll <maan@systemlinux.org>
Caused-By       : ?
Handled-By      : Linus Torvalds <torvalds@linux-foundation.org>
                  Christoph Lameter <clameter@sgi.com>
Patch           : http://lkml.org/lkml/2007/7/3/214
Status          : patch available

Subject    : OProfile issues
References : http://lkml.org/lkml/2007/6/12/207
Submitter  : Stephane Eranian <eranian@hpl.hp.com>
Handled-By : Björn Steinbrink <B.Steinbrink@gmx.de>
Patch      : http://lkml.org/lkml/2007/6/12/392
             http://lkml.org/lkml/2007/6/20/275
             http://lkml.org/lkml/2007/6/20/276
Status     : patches were suggested



Regards,
Michal

--
LOG
http://www.stardust.webpages.pl/log/

Re: 2.6.22-rc7: known regressions with patches

[Linus Torvalds]

On Tue, 3 Jul 2007, Michal Piotrowski wrote:
> 
> Subject         : inconsistent lock state
> References      : http://lkml.org/lkml/2007/7/3/195
> Last known good : ?
> Submitter       : Andre Noll <maan@systemlinux.org>
> Caused-By       : ?
> Handled-By      : Linus Torvalds <torvalds@linux-foundation.org>
>                   Christoph Lameter <clameter@sgi.com>
> Patch           : http://lkml.org/lkml/2007/7/3/214
> Status          : patch available

Ok, this one has been tested, committed, and pushed out.

		Linus

Re: 2.6.22-rc7: known regressions with patches

[Björn Steinbrink]

On 2007.07.03 18:45:24 +0200, Michal Piotrowski wrote:
> Subject    : OProfile issues
> References : http://lkml.org/lkml/2007/6/12/207
> Submitter  : Stephane Eranian <eranian@hpl.hp.com>
> Handled-By : Björn Steinbrink <B.Steinbrink@gmx.de>
> Patch      : http://lkml.org/lkml/2007/6/12/392
>              http://lkml.org/lkml/2007/6/20/275
>              http://lkml.org/lkml/2007/6/20/276
> Status     : patches were suggested

Andi said that one of the regression fixes wasn't critical for .22 and
that he wants to do a stopgap for the other regression (my patch
sucked), reverting the code to the .21 version. So you can drop the
patches and/or me here.

Thanks,
Björn

Re: 2.6.22-rc7: known regressions with patches

[Linus Torvalds]

On Tue, 3 Jul 2007, Bj?rn Steinbrink wrote:

> On 2007.07.03 18:45:24 +0200, Michal Piotrowski wrote:
> > Subject    : OProfile issues
> > References : http://lkml.org/lkml/2007/6/12/207
> > Submitter  : Stephane Eranian <eranian@hpl.hp.com>
> > Handled-By : Björn Steinbrink <B.Steinbrink@gmx.de>
> > Patch      : http://lkml.org/lkml/2007/6/12/392
> >              http://lkml.org/lkml/2007/6/20/275
> >              http://lkml.org/lkml/2007/6/20/276
> > Status     : patches were suggested
> 
> Andi said that one of the regression fixes wasn't critical for .22 and
> that he wants to do a stopgap for the other regression (my patch
> sucked), reverting the code to the .21 version. So you can drop the
> patches and/or me here.

Can you say which patch should be reverted. This thing really shouldn't 
have gone on this long, I would have hopef we had the oprofile thing 
sorted out already..

		Linus

Re: 2.6.22-rc7: known regressions with patches

[Björn Steinbrink]

On 2007.07.03 14:42:25 -0700, Linus Torvalds wrote:
> 
> 
> On Tue, 3 Jul 2007, Bj?rn Steinbrink wrote:
> > Andi said that one of the regression fixes wasn't critical for .22 and
> > that he wants to do a stopgap for the other regression (my patch
> > sucked), reverting the code to the .21 version. So you can drop the
> > patches and/or me here.
> 
> Can you say which patch should be reverted. This thing really shouldn't 
> have gone on this long, I would have hopef we had the oprofile thing 
> sorted out already..

That would be commit 09198e68501a7e34737cd9264d266f42429abcdc, for which
there are already a few fixes in your tree. Andi, did you intent to
fully revert that, or just certain parts of it?

Björn

Re: 2.6.22-rc7: known regressions with patches

[Andi Kleen]

On Wednesday 04 July 2007 00:12:10 Björn Steinbrink wrote:
> On 2007.07.03 14:42:25 -0700, Linus Torvalds wrote:
> > 
> > 
> > On Tue, 3 Jul 2007, Bj?rn Steinbrink wrote:
> > > Andi said that one of the regression fixes wasn't critical for .22 and
> > > that he wants to do a stopgap for the other regression (my patch
> > > sucked), reverting the code to the .21 version. So you can drop the
> > > patches and/or me here.
> > 
> > Can you say which patch should be reverted. This thing really shouldn't 
> > have gone on this long, I would have hopef we had the oprofile thing 
> > sorted out already..
> 
> That would be commit 09198e68501a7e34737cd9264d266f42429abcdc, for which
> there are already a few fixes in your tree. Andi, did you intent to
> fully revert that, or just certain parts of it?

Just two functions, but in a different file. Here's the patch.

Linus, also what about the revert of the HPET reservation? That would
fix a clear regression too.

-Andi

Revert perfctr reservation to 2.6.21 state

With this change it works again when the nmi watchdog is disabled.

Signed-off-by: Andi Kleen <ak@suse.de>

Index: linux/arch/i386/kernel/cpu/perfctr-watchdog.c
===================================================================
--- linux.orig/arch/i386/kernel/cpu/perfctr-watchdog.c
+++ linux/arch/i386/kernel/cpu/perfctr-watchdog.c
@@ -55,14 +55,45 @@ static DEFINE_PER_CPU(struct nmi_watchdo
 /* converts an msr to an appropriate reservation bit */
 static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)
 {
-	return wd_ops ? msr - wd_ops->perfctr : 0;
+	/* returns the bit offset of the performance counter register */
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_AMD:
+		return (msr - MSR_K7_PERFCTR0);
+	case X86_VENDOR_INTEL:
+		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+			return (msr - MSR_ARCH_PERFMON_PERFCTR0);
+
+		switch (boot_cpu_data.x86) {
+		case 6:
+			return (msr - MSR_P6_PERFCTR0);
+		case 15:
+			return (msr - MSR_P4_BPU_PERFCTR0);
+		}
+	}
+	return 0;
 }
 
 /* converts an msr to an appropriate reservation bit */
 /* returns the bit offset of the event selection register */
 static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr)
 {
-	return wd_ops ? msr - wd_ops->evntsel : 0;
+	/* returns the bit offset of the event selection register */
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_AMD:
+		return (msr - MSR_K7_EVNTSEL0);
+	case X86_VENDOR_INTEL:
+		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+			return (msr - MSR_ARCH_PERFMON_EVENTSEL0);
+
+		switch (boot_cpu_data.x86) {
+		case 6:
+			return (msr - MSR_P6_EVNTSEL0);
+		case 15:
+			return (msr - MSR_P4_BSU_ESCR0);
+		}
+	}
+	return 0;
+
 }
 
 /* checks for a bit availability (hack for oprofile) */

Re: 2.6.22-rc7: known regressions with patches

[Linus Torvalds]

On Wed, 4 Jul 2007, Andi Kleen wrote:
> 
> Linus, also what about the revert of the HPET reservation? That would
> fix a clear regression too.

Thanks for reminding me. It probably isn't much of a regression any more 
(since we added the code to not use the HPET when it doesn't seem to be 
working), but yes, that should go in too.

Applied and pushed out. Now we just need people to test and verify that 
the regressions are gone..

		Linus