linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Marek Behún" <kabel@kernel.org>
To: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci@vger.kernel.org, pali@kernel.org,
	stable@vger.kernel.org, maz@kernel.org
Subject: Re: [PATCH 06/13] PCI: aardvark: Do not clear status bits of masked interrupts
Date: Mon, 4 Oct 2021 17:18:23 +0200	[thread overview]
Message-ID: <20211004171823.0288684e@thinkpad> (raw)
In-Reply-To: <20211004140653.GB24914@lpieralisi>

On Mon, 4 Oct 2021 15:06:53 +0100
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote:

> [+Marc - always better to have his eyes on IRQ handling code]
> 
> > -	if (!isr0_status && !isr1_status) {
> > -		advk_writel(pcie, isr0_val, PCIE_ISR0_REG);
> > -		advk_writel(pcie, isr1_val, PCIE_ISR1_REG);  
> 
> This looks fine - on the other hand if no interrupt is set in the status
> registers (that are filtered with the masks) we are dealing with a
> spurious IRQ right ? Just gauging how severe this is.

Yes, spurious IRQ can really happen.

Patch 7 in this series fixes an issue where aardvark does not mask all
interrupts, and then kernel can think that an interrupt is masked but
it really isn't.

Also, some interrupts may be masked by the user of the emulated bridge
(some other driver), so that they can be polled. But if we clear all of
them in the status, even the masked ones, then the other driver which
is polling will always get a zero.

Marek

  reply	other threads:[~2021-10-04 15:18 UTC|newest]

Thread overview: 47+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-01 19:58 [PATCH 00/13] PCI: aardvark controller fixes Marek Behún
2021-10-01 19:58 ` [PATCH 01/13] PCI: Add PCI_EXP_DEVCTL_PAYLOAD_* macros Marek Behún
2021-10-02 16:05   ` Bjorn Helgaas
2021-10-04  8:43   ` Lorenzo Pieralisi
2021-10-04  9:32     ` Marek Behún
2021-10-04  9:35       ` Lorenzo Pieralisi
2021-10-01 19:58 ` [PATCH 02/13] PCI: aardvark: Fix PCIe Max Payload Size setting Marek Behún
2021-10-03 17:44   ` Marek Behún
2021-10-01 19:58 ` [PATCH 03/13] PCI: aardvark: Don't spam about PIO Response Status Marek Behún
2021-10-01 19:58 ` [PATCH 04/13] PCI: aardvark: Fix preserving PCI_EXP_RTCTL_CRSSVE flag on emulated bridge Marek Behún
2021-10-01 19:58 ` [PATCH 05/13] PCI: aardvark: Fix configuring Reference clock Marek Behún
2021-10-01 19:58 ` [PATCH 06/13] PCI: aardvark: Do not clear status bits of masked interrupts Marek Behún
2021-10-04 14:06   ` Lorenzo Pieralisi
2021-10-04 15:18     ` Marek Behún [this message]
2021-10-04 15:31     ` Marc Zyngier
2021-10-05 12:13       ` Marek Behún
2021-10-05 12:42         ` Marc Zyngier
2021-10-05 13:15           ` Pali Rohár
2021-10-05 15:42             ` Marc Zyngier
2021-10-05 18:48               ` Pali Rohár
2021-10-05 16:04             ` Lorenzo Pieralisi
2021-10-01 19:58 ` [PATCH 07/13] PCI: aardvark: Do not unmask unused interrupts Marek Behún
2021-10-01 19:58 ` [PATCH 08/13] PCI: aardvark: Deduplicate code in advk_pcie_rd_conf() Marek Behún
2021-10-01 19:58 ` [PATCH 09/13] PCI: aardvark: Implement re-issuing config requests on CRS response Marek Behún
2021-10-02 16:35   ` Bjorn Helgaas
2021-10-04  7:21     ` Marek Behún
2021-10-04  8:53       ` Lorenzo Pieralisi
2021-10-04 10:19         ` Marek Behún
2021-10-05 19:28           ` Bjorn Helgaas
2021-10-05 22:45             ` Marek Behún
2021-10-11 18:15               ` Usage of PCBIOS_* macros (Was: Re: [PATCH 09/13] PCI: aardvark: Implement re-issuing config requests on CRS response) Pali Rohár
2021-10-11 20:58                 ` Bjorn Helgaas
2021-10-06 16:29             ` [PATCH 09/13] PCI: aardvark: Implement re-issuing config requests on CRS response Lorenzo Pieralisi
2021-10-06 20:13               ` Bjorn Helgaas
2021-10-07 11:51                 ` Lorenzo Pieralisi
2021-10-07 12:36                   ` Marek Behún
2021-10-07 19:25                     ` Bjorn Helgaas
2021-10-01 19:58 ` [PATCH 10/13] PCI: aardvark: Simplify initialization of rootcap on virtual bridge Marek Behún
2021-10-04  9:44   ` Lorenzo Pieralisi
2021-10-04  9:56     ` Marek Behún
2021-10-04 10:10       ` Lorenzo Pieralisi
2021-10-01 19:58 ` [PATCH 11/13] PCI: aardvark: Fix link training Marek Behún
2021-10-01 19:58 ` [PATCH 12/13] PCI: aardvark: Fix checking for link up via LTSSM state Marek Behún
2021-10-04 13:35   ` Lorenzo Pieralisi
2021-10-01 19:58 ` [PATCH 13/13] PCI: aardvark: Fix reporting Data Link Layer Link Active Marek Behún
2021-10-04  9:53 ` [PATCH 00/13] PCI: aardvark controller fixes Lorenzo Pieralisi
2021-10-04 10:40   ` Marek Behún

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=20211004171823.0288684e@thinkpad \
    --to=kabel@kernel.org \
    --cc=bhelgaas@google.com \
    --cc=linux-pci@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=maz@kernel.org \
    --cc=pali@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=thomas.petazzoni@bootlin.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).