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Hi, I'm resending this patch series. It's rediffed against linux-next branch of Joel's git tree. The first four patches are obvious fixes of deadlocks in quota code and should go in as soon as possible. The other three patches implement lockdep support for OCFS2 cluster locks. So you can have a look whether the code make sence to you and possibly merge them. They should be NOP when

...4c90c 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -742,6 +742,13 @@ noinstr void idtentry_exit_nmi(struct pt_regs *regs, bool restore) __nmi_exit(); } +noinstr void idtentry_validate_ist(struct pt_regs *regs) +{ + if ((regs->sp & ~(EXCEPTION_STKSZ-1)) == + (_RET_IP_ & ~(EXCEPTION_STKSZ-1))) + die("IST stack recursion", regs, 0); +} + #ifdef CONFIG_XEN_PV #ifndef CONFIG_PREEMPTION /* diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 4e399f120ff8..974c1a4eacbb 100644 --- a/arch/x86/include/asm/idtentry.h +++ b...

On Tue, Jun 23, 2020 at 04:59:14PM +0200, Joerg Roedel wrote: > On Tue, Jun 23, 2020 at 04:53:44PM +0200, Peter Zijlstra wrote: > > +noinstr void idtentry_validate_ist(struct pt_regs *regs) > > +{ > > + if ((regs->sp & ~(EXCEPTION_STKSZ-1)) == > > + (_RET_IP_ & ~(EXCEPTION_STKSZ-1))) > > + die("IST stack recursion", regs, 0); > > +} > > Yes, this is a start, it doesn't cover the case where the NMI stack is > in-between, so I think you need to walk down regs->sp too. That shouldn't be possible with the cur...

Hi, here comes the next version of OCFS2 lockdep support. I've dropped patches with fixes from the series since they were already merged. As Joel suggested, I've simplified the main patch a bit so that we don't have ifdefs around lock declarations and there are also a few other minor improvements. Honza

On Tue, Jun 23, 2020 at 04:53:44PM +0200, Peter Zijlstra wrote: > +noinstr void idtentry_validate_ist(struct pt_regs *regs) > +{ > + if ((regs->sp & ~(EXCEPTION_STKSZ-1)) == > + (_RET_IP_ & ~(EXCEPTION_STKSZ-1))) > + die("IST stack recursion", regs, 0); > +} Yes, this is a start, it doesn't cover the case where the NMI stack is in-between, so I think you need to walk down regs->sp too. The dumpstack code already has some logic for this. Joerg

...e, Jun 23, 2020 at 04:59:14PM +0200, Joerg Roedel wrote: >> On Tue, Jun 23, 2020 at 04:53:44PM +0200, Peter Zijlstra wrote: >>> +noinstr void idtentry_validate_ist(struct pt_regs *regs) >>> +{ >>> + if ((regs->sp & ~(EXCEPTION_STKSZ-1)) == >>> + (_RET_IP_ & ~(EXCEPTION_STKSZ-1))) >>> + die("IST stack recursion", regs, 0); >>> +} >> Yes, this is a start, it doesn't cover the case where the NMI stack is >> in-between, so I think you need to walk down regs->sp too. > That shouldn't be possible...

..., 2020 at 04:59:14PM +0200, Joerg Roedel wrote: > > On Tue, Jun 23, 2020 at 04:53:44PM +0200, Peter Zijlstra wrote: > > > +noinstr void idtentry_validate_ist(struct pt_regs *regs) > > > +{ > > > + if ((regs->sp & ~(EXCEPTION_STKSZ-1)) == > > > + (_RET_IP_ & ~(EXCEPTION_STKSZ-1))) > > > + die("IST stack recursion", regs, 0); > > > +} > > > > Yes, this is a start, it doesn't cover the case where the NMI stack is > > in-between, so I think you need to walk down regs->sp too. > > That sho...

On Tue, Jun 23, 2020 at 02:52:01PM +0200, Peter Zijlstra wrote: > On Tue, Jun 23, 2020 at 02:04:33PM +0200, Joerg Roedel wrote: > > No, the recursion check is fine, because overwriting an already used IST > > stack doesn't matter (as long as it can be detected) if we are going to > > panic anyway. It doesn't matter because the kernel will not leave the > >

Hi, the first four patches in this series fix locking problems in OCFS2 quota code (three of them can lead to potential deadlocks). The fifth patch reorders ip_alloc_sem for directories to be acquired before localalloc locks. Mark would you please merge these? The last two patches implement lockdep annotations for OCFS2 cluster locks. We annotate all the cluster locks except for special ones