public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: Michael Ellerman <mpe@ellerman•id.au>
To: Nicholas Piggin <npiggin@gmail•com>, linuxppc-dev@lists•ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail•com>
Subject: Re: [PATCH v4 04/16] powerpc/64s/exceptions: machine check reconcile irq state
Date: Fri, 08 May 2020 23:39:03 +1000	[thread overview]
Message-ID: <878si2czrc.fsf@mpe.ellerman.id.au> (raw)
In-Reply-To: <20200508043408.886394-5-npiggin@gmail.com>

Nicholas Piggin <npiggin@gmail•com> writes:

> pseries fwnmi machine check code pops the soft-irq checks in rtas_call
> (after the previous patch to remove rtas_token from this call path).
             ^
             I changed this to "next" which I think is what you meant?

cheers

> Rather than play whack a mole with these and forever having fragile
> code, it seems better to have the early machine check handler perform
> the same kind of reconcile as the other NMI interrupts.
>
>   WARNING: CPU: 0 PID: 493 at arch/powerpc/kernel/irq.c:343
>   CPU: 0 PID: 493 Comm: a Tainted: G        W
>   NIP:  c00000000001ed2c LR: c000000000042c40 CTR: 0000000000000000
>   REGS: c0000001fffd38b0 TRAP: 0700   Tainted: G        W
>   MSR:  8000000000021003 <SF,ME,RI,LE>  CR: 28000488  XER: 00000000
>   CFAR: c00000000001ec90 IRQMASK: 0
>   GPR00: c000000000043820 c0000001fffd3b40 c0000000012ba300 0000000000000000
>   GPR04: 0000000048000488 0000000000000000 0000000000000000 00000000deadbeef
>   GPR08: 0000000000000080 0000000000000000 0000000000000000 0000000000001001
>   GPR12: 0000000000000000 c0000000014a0000 0000000000000000 0000000000000000
>   GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
>   GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
>   GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
>   GPR28: 0000000000000000 0000000000000001 c000000001360810 0000000000000000
>   NIP [c00000000001ed2c] arch_local_irq_restore.part.0+0xac/0x100
>   LR [c000000000042c40] unlock_rtas+0x30/0x90
>   Call Trace:
>   [c0000001fffd3b40] [c000000001360810] 0xc000000001360810 (unreliable)
>   [c0000001fffd3b60] [c000000000043820] rtas_call+0x1c0/0x280
>   [c0000001fffd3bb0] [c0000000000dc328] fwnmi_release_errinfo+0x38/0x70
>   [c0000001fffd3c10] [c0000000000dcd8c] pseries_machine_check_realmode+0x1dc/0x540
>   [c0000001fffd3cd0] [c00000000003fe04] machine_check_early+0x54/0x70
>   [c0000001fffd3d00] [c000000000008384] machine_check_early_common+0x134/0x1f0
>   --- interrupt: 200 at 0x13f1307c8
>       LR = 0x7fff888b8528
>   Instruction dump:
>   60000000 7d2000a6 71298000 41820068 39200002 7d210164 4bffff9c 60000000
>   60000000 7d2000a6 71298000 4c820020 <0fe00000> 4e800020 60000000 60000000
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail•com>
> ---
>  arch/powerpc/kernel/exceptions-64s.S | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
>
> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
> index a42b73efb1a9..072772803b7c 100644
> --- a/arch/powerpc/kernel/exceptions-64s.S
> +++ b/arch/powerpc/kernel/exceptions-64s.S
> @@ -1116,11 +1116,30 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
>  	li	r10,MSR_RI
>  	mtmsrd	r10,1
>  
> +	/*
> +	 * Set IRQS_ALL_DISABLED and save PACAIRQHAPPENED (see
> +	 * system_reset_common)
> +	 */
> +	li	r10,IRQS_ALL_DISABLED
> +	stb	r10,PACAIRQSOFTMASK(r13)
> +	lbz	r10,PACAIRQHAPPENED(r13)
> +	std	r10,RESULT(r1)
> +	ori	r10,r10,PACA_IRQ_HARD_DIS
> +	stb	r10,PACAIRQHAPPENED(r13)
> +
>  	addi	r3,r1,STACK_FRAME_OVERHEAD
>  	bl	machine_check_early
>  	std	r3,RESULT(r1)	/* Save result */
>  	ld	r12,_MSR(r1)
>  
> +	/*
> +	 * Restore soft mask settings.
> +	 */
> +	ld	r10,RESULT(r1)
> +	stb	r10,PACAIRQHAPPENED(r13)
> +	ld	r10,SOFTE(r1)
> +	stb	r10,PACAIRQSOFTMASK(r13)
> +
>  #ifdef CONFIG_PPC_P7_NAP
>  	/*
>  	 * Check if thread was in power saving mode. We come here when any
> -- 
> 2.23.0

  reply	other threads:[~2020-05-08 13:58 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-08  4:33 [PATCH v4 00/16] powerpc: machine check and system reset fixes Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 01/16] powerpc/64s/exception: Fix machine check no-loss idle wakeup Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 02/16] powerpc/64s/exceptions: Fix in_mce accounting in unrecoverable path Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 03/16] powerpc/64s/exceptions: Change irq reconcile for NMIs from reusing _DAR to RESULT Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 04/16] powerpc/64s/exceptions: machine check reconcile irq state Nicholas Piggin
2020-05-08 13:39   ` Michael Ellerman [this message]
2020-05-09  7:48     ` Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 05/16] powerpc/pseries/ras: avoid calling rtas_token in NMI paths Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 06/16] powerpc/pseries/ras: FWNMI_VALID off by one Nicholas Piggin
2020-05-08  4:33 ` [PATCH v4 07/16] powerpc/pseries/ras: fwnmi avoid modifying r3 in error case Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 08/16] powerpc/pseries/ras: fwnmi sreset should not interlock Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 09/16] powerpc/pseries: limit machine check stack to 4GB Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 10/16] powerpc/pseries: machine check use rtas_call_unlocked with args on stack Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 11/16] powerpc/64s: machine check interrupt update NMI accounting Nicholas Piggin
2020-05-09  3:13   ` kbuild test robot
2020-05-09  7:50     ` Nicholas Piggin
2020-05-11  9:50       ` Michael Ellerman
2020-05-08  4:34 ` [PATCH v4 12/16] powerpc: implement ftrace_enabled helper Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 13/16] powerpc/64s: machine check do not trace real-mode handler Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 14/16] powerpc/traps: system reset do not trace Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 15/16] powerpc/traps: make unrecoverable NMIs die instead of panic Nicholas Piggin
2020-05-08  4:34 ` [PATCH v4 16/16] powerpc/traps: Machine check fix RI=0 recoverability check Nicholas Piggin
2020-05-20 11:00 ` [PATCH v4 00/16] powerpc: machine check and system reset fixes Michael Ellerman

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=878si2czrc.fsf@mpe.ellerman.id.au \
    --to=mpe@ellerman$(echo .)id.au \
    --cc=linuxppc-dev@lists$(echo .)ozlabs.org \
    --cc=npiggin@gmail$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox