Re: 4.14.9 with CONFIG_MCORE2 fails to boot

[Alexander Tsoy]

Ð ÐÑ, 29/12/2017 Ð 10:17 +0100, Greg KH ÐÐÑÐÑ:
> On Thu, Dec 28, 2017 at 12:33:22PM +0300, Alexander Tsoy wrote:
> > Hello,
> > 
> > 4.14.9 fails to boot if CONFIG_MCORE2 is enabled and when compiled
> > with
> > gcc 6+. More details in the following bug reports:
> > https://bugzilla.kernel.org/show_bug.cgi?id=198263
> > https://bugs.gentoo.org/642268
> > 
> > I bisected it to the commit below:
> > 
> > $ git bisect good
> > 2bc9fa0beaf10206a778f02e9e5cb62f50345b1a is the first bad commit
> > commit 2bc9fa0beaf10206a778f02e9e5cb62f50345b1a
> > Author: Andy Lutomirski <luto@xxxxxxxxxx>
> > Date:ÂÂÂMon Dec 4 15:07:23 2017 +0100
> > 
> > ÂÂÂÂx86/entry/64: Use a per-CPU trampoline stack for IDT entries
> > 
> > ÂÂÂÂcommit 7f2590a110b837af5679d08fc25c6227c5a8c497 upstream.
> > 
> > ÂÂÂÂHistorically, IDT entries from usermode have always gone
> > directly
> > ÂÂÂÂto the running task's kernel stack.ÂÂRearrange it so that we
> > enter
> > on
> > ÂÂÂÂa per-CPU trampoline stack and then manually switch to the
> > task's
> > stack.
> > ÂÂÂÂThis touches a couple of extra cachelines, but it gives us a
> > chance
> > ÂÂÂÂto run some code before we touch the kernel stack.
> > 
> > ÂÂÂÂThe asm isn't exactly beautiful, but I think that fully
> > refactoring
> > ÂÂÂÂit can wait.
> > 
> > ÂÂÂÂSigned-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
> > ÂÂÂÂSigned-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > ÂÂÂÂReviewed-by: Borislav Petkov <bp@xxxxxxx>
> > ÂÂÂÂReviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > ÂÂÂÂCc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
> > ÂÂÂÂCc: Borislav Petkov <bp@xxxxxxxxx>
> > ÂÂÂÂCc: Borislav Petkov <bpetkov@xxxxxxx>
> > ÂÂÂÂCc: Brian Gerst <brgerst@xxxxxxxxx>
> > ÂÂÂÂCc: Dave Hansen <dave.hansen@xxxxxxxxx>
> > ÂÂÂÂCc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> > ÂÂÂÂCc: David Laight <David.Laight@xxxxxxxxxx>
> > ÂÂÂÂCc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
> > ÂÂÂÂCc: Eduardo Valentin <eduval@xxxxxxxxxx>
> > ÂÂÂÂCc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> > ÂÂÂÂCc: H. Peter Anvin <hpa@xxxxxxxxx>
> > ÂÂÂÂCc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> > ÂÂÂÂCc: Juergen Gross <jgross@xxxxxxxx>
> > ÂÂÂÂCc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> > ÂÂÂÂCc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > ÂÂÂÂCc: Rik van Riel <riel@xxxxxxxxxx>
> > ÂÂÂÂCc: Will Deacon <will.deacon@xxxxxxx>
> > ÂÂÂÂCc: aliguori@xxxxxxxxxx
> > ÂÂÂÂCc: daniel.gruss@xxxxxxxxxxxxxx
> > ÂÂÂÂCc: hughd@xxxxxxxxxx
> > ÂÂÂÂCc: keescook@xxxxxxxxxx
> > ÂÂÂÂLink: https://lkml.kernel.org/r/20171204150606.225330557@linutr
> > onix
> > .de
> > ÂÂÂÂSigned-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
> > ÂÂÂÂSigned-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > 
> > :040000 040000 275d4746936a9e521a2b5041856f7dc1d1820dc6
> > 8f8e869fd59c3dd781dceffa76e53e41d733a0cf MÂÂÂÂÂÂarch
> > 
> > $ git bisect log
> > git bisect start
> > # bad: [dad5c1402c570cd07a80113784bc20a7f930c8ae] Linux 4.14.9
> > git bisect bad dad5c1402c570cd07a80113784bc20a7f930c8ae
> > # good: [7b3775017f4e6b87dfd2c7f63d1eaf057948f31d] Linux 4.14.8
> > git bisect good 7b3775017f4e6b87dfd2c7f63d1eaf057948f31d
> > # good: [d120cd749ef9770ee98b708a83b49547dcf1c0e1] x86/entry/64:
> > Separate cpu_current_top_of_stack from TSS.sp0
> > git bisect good d120cd749ef9770ee98b708a83b49547dcf1c0e1
> > # bad: [97f41b41c432e5a80c91445d92c2f4b729984d36] powerpc/xmon:
> > Avoid
> > tripping SMP hardlockup watchdog
> > git bisect bad 97f41b41c432e5a80c91445d92c2f4b729984d36
> > # bad: [bfd66a406fe7e590055c1d6714adc697f18664c8] PCI: Avoid bus
> > reset
> > if bridge itself is broken
> > git bisect bad bfd66a406fe7e590055c1d6714adc697f18664c8
> > # bad: [8388d287e361a2fd0a39bece30a736d692d5c3d8] x86/cpufeatures:
> > Make
> > CPU bugs sticky
> > git bisect bad 8388d287e361a2fd0a39bece30a736d692d5c3d8
> > # bad: [bb568391775d4a840992e2d2493f39d6e86401e3] x86/entry/64:
> > Move
> > the IST stacks into struct cpu_entry_area
> > git bisect bad bb568391775d4a840992e2d2493f39d6e86401e3
> > # bad: [2bc9fa0beaf10206a778f02e9e5cb62f50345b1a] x86/entry/64: Use
> > a
> > per-CPU trampoline stack for IDT entries
> > git bisect bad 2bc9fa0beaf10206a778f02e9e5cb62f50345b1a
> > # good: [c3dbef1bd0f7eb09daf49409ea533aa1b0eeb82e] x86/espfix/64:
> > Stop
> > assuming that pt_regs is on the entry stack
> > git bisect good c3dbef1bd0f7eb09daf49409ea533aa1b0eeb82e
> > # first bad commit: [2bc9fa0beaf10206a778f02e9e5cb62f50345b1a]
> > x86/entry/64: Use a per-CPU trampoline stack for IDT entries
> 
> Thanks for letting us know.ÂÂDoes Linus's current tree also have this
> same problem for you?

Just tested Linus's master branch and it have the same problem. All I
can catch with a serial console is the following:

[ÂÂÂÂ0.000000] ACPI BIOS Warning[ÂÂÂÂ0.498898] Expanded resource
conflict with PCI Bus 0000:00