linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com>
To: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH v2 43/52] powerpc/64s/exception: machine check early only runs in HV mode
Date: Thu, 20 Jun 2019 15:23:29 +0530	[thread overview]
Message-ID: <20190620095329.rvrwxgtjsgkc4k5t@in.ibm.com> (raw)
In-Reply-To: <20190620051459.29573-44-npiggin@gmail.com>

On 2019-06-20 15:14:50 Thu, Nicholas Piggin wrote:
> machine_check_common_early and machine_check_handle_early only run in
> HVMODE. Remove dead code.

That's not true. For pseries guest with FWNMI enabled hypervisor,
machine_check_common_early gets called in non-HV mode as well.

   machine_check_fwnmi
     machine_check_common_early
       machine_check_handle_early
         machine_check_early
           pseries_machine_check_realmode

Thanks,
-Mahesh.

> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  arch/powerpc/kernel/exceptions-64s.S | 38 +++++-----------------------
>  1 file changed, 6 insertions(+), 32 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
> index b12755a4f884..f3362adc99e6 100644
> --- a/arch/powerpc/kernel/exceptions-64s.S
> +++ b/arch/powerpc/kernel/exceptions-64s.S
> @@ -1014,10 +1014,7 @@ TRAMP_REAL_BEGIN(machine_check_common_early)
>  	/* Save r9 through r13 from EXMC save area to stack frame. */
>  	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
>  	mfmsr	r11			/* get MSR value */
> -BEGIN_FTR_SECTION
> -	ori	r11,r11,MSR_ME		/* turn on ME bit */
> -END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
> -	ori	r11,r11,MSR_RI		/* turn on RI bit */
> +	ori	r11,r11,MSR_ME|MSR_RI	/* turn on ME, RI */
>  	LOAD_HANDLER(r12, machine_check_handle_early)
>  1:	mtspr	SPRN_SRR0,r12
>  	mtspr	SPRN_SRR1,r11
> @@ -1124,11 +1121,8 @@ EXC_COMMON_BEGIN(machine_check_handle_early)
>  	bl	machine_check_early
>  	std	r3,RESULT(r1)	/* Save result */
>  	ld	r12,_MSR(r1)
> -BEGIN_FTR_SECTION
> -	b	4f
> -END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
> 
> -#ifdef	CONFIG_PPC_P7_NAP
> +#ifdef CONFIG_PPC_P7_NAP
>  	/*
>  	 * Check if thread was in power saving mode. We come here when any
>  	 * of the following is true:
> @@ -1141,7 +1135,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
>  BEGIN_FTR_SECTION
>  	rlwinm.	r11,r12,47-31,30,31
>  	bne	machine_check_idle_common
> -END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
> +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
>  #endif
> 
>  	/*
> @@ -1150,12 +1144,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
>  	 */
>  	rldicl.	r11,r12,4,63		/* See if MC hit while in HV mode. */
>  	beq	5f
> -4:	andi.	r11,r12,MSR_PR		/* See if coming from user. */
> +	andi.	r11,r12,MSR_PR		/* See if coming from user. */
>  	bne	9f			/* continue in V mode if we are. */
> 
>  5:
>  #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
> -BEGIN_FTR_SECTION
>  	/*
>  	 * We are coming from kernel context. Check if we are coming from
>  	 * guest. if yes, then we can continue. We will fall through
> @@ -1164,7 +1157,6 @@ BEGIN_FTR_SECTION
>  	lbz	r11,HSTATE_IN_GUEST(r13)
>  	cmpwi	r11,0			/* Check if coming from guest */
>  	bne	9f			/* continue if we are. */
> -END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
>  #endif
>  	/*
>  	 * At this point we are not sure about what context we come from.
> @@ -1199,7 +1191,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
>  	cmpdi	r3,0		/* see if we handled MCE successfully */
> 
>  	beq	1b		/* if !handled then panic */
> -BEGIN_FTR_SECTION
> +
>  	/*
>  	 * Return from MC interrupt.
>  	 * Queue up the MCE event so that we can log it later, while
> @@ -1208,18 +1200,7 @@ BEGIN_FTR_SECTION
>  	bl	machine_check_queue_event
>  	MACHINE_CHECK_HANDLER_WINDUP
>  	RFI_TO_USER_OR_KERNEL
> -FTR_SECTION_ELSE
> -	/*
> -	 * pSeries: Return from MC interrupt. Before that stay on emergency
> -	 * stack and call machine_check_exception to log the MCE event.
> -	 */
> -	LOAD_HANDLER(r10,mce_return)
> -	mtspr	SPRN_SRR0,r10
> -	ld	r10,PACAKMSR(r13)
> -	mtspr	SPRN_SRR1,r10
> -	RFI_TO_KERNEL
> -	b	.
> -ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
> +
>  9:
>  	/* Deliver the machine check to host kernel in V mode. */
>  	MACHINE_CHECK_HANDLER_WINDUP
> @@ -1238,13 +1219,6 @@ EXC_COMMON_BEGIN(unrecover_mce)
>  	bl	unrecoverable_exception
>  	b	1b
> 
> -EXC_COMMON_BEGIN(mce_return)
> -	/* Invoke machine_check_exception to print MCE event and return. */
> -	addi	r3,r1,STACK_FRAME_OVERHEAD
> -	bl	machine_check_exception
> -	MACHINE_CHECK_HANDLER_WINDUP
> -	RFI_TO_KERNEL
> -	b	.
> 
>  EXC_REAL_BEGIN(data_access, 0x300, 0x80)
>  	EXCEPTION_PROLOG_0 PACA_EXGEN
> -- 
> 2.20.1
> 

-- 
Mahesh J Salgaonkar


  reply	other threads:[~2019-06-20  9:55 UTC|newest]

Thread overview: 59+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-20  5:14 [PATCH v2 00/52] powerpc/64s interrupt handler cleanups, gasification Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 01/52] powerpc/64s/exception: fix line wrap and semicolon inconsistencies in macros Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 02/52] powerpc/64s/exception: remove H concatenation for EXC_HV variants Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 03/52] powerpc/64s/exception: consolidate EXCEPTION_PROLOG_2 with _NORI variant Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 04/52] powerpc/64s/exception: move and tidy EXCEPTION_PROLOG_2 variants Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 05/52] powerpc/64s/exception: fix sreset KVM test code Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 06/52] powerpc/64s/exception: remove the "extra" macro parameter Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 07/52] powerpc/64s/exception: consolidate maskable and non-maskable prologs Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 08/52] powerpc/64s/exception: merge KVM handler and skip variants Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 09/52] powerpc/64s/exception: KVM handler can set the HSRR trap bit Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 10/52] powerpc/64s/exception: Make EXCEPTION_PROLOG_0 a gas macro for consistency with others Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 11/52] powerpc/64s/exception: Move EXCEPTION_COMMON handler and return branches into callers Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 12/52] powerpc/64s/exception: Move EXCEPTION_COMMON additions " Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 13/52] powerpc/64s/exception: unwind exception-64s.h macros Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 14/52] powerpc/64s/exception: improve 0x500 handler code Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 15/52] powerpc/64s/exception: move EXCEPTION_PROLOG_2* to a more logical place Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 16/52] powerpc/64s/exception: remove STD_EXCEPTION_COMMON variants Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 17/52] powerpc/64s/exception: move KVM related code together Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 18/52] powerpc/64s/exception: move exception-64s.h code to exception-64s.S where it is used Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 19/52] powerpc/64s/exception: move head-64.h " Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 20/52] powerpc/64s/exception: remove __BRANCH_TO_KVM Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 21/52] powerpc/64s/exception: remove unused BRANCH_TO_COMMON Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 22/52] powerpc/64s/exception: use a gas macro for system call handler code Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 23/52] powerpc/64s/exception: fix indenting irregularities Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 24/52] powerpc/64s/exception: generate regs clear instructions using .rept Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 25/52] powerpc/64s/exception: remove bad stack branch Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 26/52] powerpc/64s/exception: remove pointless EXCEPTION_PROLOG macro indirection Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 27/52] powerpc/64s/exception: move paca save area offsets into exception-64s.S Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 28/52] powerpc/64s/exception: clean up system call entry Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 29/52] powerpc/64s/exception: avoid SPR RAW scoreboard stall in real mode entry Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 30/52] powerpc/64s/exception: optimise system_reset for idle, clean up non-idle case Nicholas Piggin
2019-06-20  5:41   ` Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 31/52] powerpc/64s/exception: mtmsrd L=1 cleanup Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 32/52] powerpc/64s/exception: windup use r9 consistently to restore SPRs Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 33/52] powerpc/64s/exception: move machine check windup in_mce handling Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 34/52] powerpc/64s/exception: simplify hmi windup code Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 35/52] powerpc/64s/exception: shuffle windup code around Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 36/52] powerpc/64s/exception: use common macro for windup Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 37/52] powerpc/64s/exception: add dar and dsisr options to exception macro Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 38/52] powerpc/64s/exception: machine check use standard macros to save dar/dsisr Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 39/52] powerpc/64s/exception: denorm handler use standard scratch save macro Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 40/52] powerpc/64s/exception: move SET_SCRATCH0 into EXCEPTION_PROLOG_0 Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 41/52] powerpc/tm: update comment about interrupt re-entrancy Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 42/52] powerpc/64s/exception: machine check fwnmi does not trigger when in HV mode Nicholas Piggin
2019-06-20  9:26   ` Mahesh Jagannath Salgaonkar
2019-06-20  9:50     ` Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 43/52] powerpc/64s/exception: machine check early only runs " Nicholas Piggin
2019-06-20  9:53   ` Mahesh J Salgaonkar [this message]
2019-06-20 10:16     ` Nicholas Piggin
2019-06-20 10:57       ` Mahesh Jagannath Salgaonkar
2019-06-20  5:14 ` [PATCH v2 44/52] powerpc/64s/exception: separate pseries and powernv mce delivery paths Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 45/52] powerpc/64s/exception: machine check windup restore cfar for host delivery Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 46/52] powerpc/64s/exception: fix machine check early should not set AMR Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 47/52] powerpc/64s/exception: machine check restructure handler to be more regular Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 48/52] powerpc/64s/exception: simplify machine check early path Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 49/52] powerpc/64s/exceptions: machine check move unrecoverable handling out of line Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 50/52] powerpc/64s/exception: untangle early machine check handler Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 51/52] powerpc/64s/exception: machine check improve branch labels Nicholas Piggin
2019-06-20  5:14 ` [PATCH v2 52/52] powerpc/64s/exception: add missing branch to self after RFI Nicholas Piggin

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=20190620095329.rvrwxgtjsgkc4k5t@in.ibm.com \
    --to=mahesh@linux.vnet.ibm.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=npiggin@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
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;
as well as URLs for NNTP newsgroup(s).