lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 14 Jan 2015 08:51:37 +0100 From: Uwe Kleine-König <u.kleine-koenig@...gutronix.de> To: Ray Jui <rjui@...adcom.com> Cc: Wolfram Sang <wsa@...-dreams.de>, Rob Herring <robh+dt@...nel.org>, Pawel Moll <pawel.moll@....com>, Mark Rutland <mark.rutland@....com>, Ian Campbell <ijc+devicetree@...lion.org.uk>, Kumar Gala <galak@...eaurora.org>, Grant Likely <grant.likely@...aro.org>, Christian Daudt <bcm@...thebug.org>, Matt Porter <mporter@...aro.org>, Florian Fainelli <f.fainelli@...il.com>, Russell King <linux@....linux.org.uk>, Scott Branden <sbranden@...adcom.com>, linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org, bcm-kernel-feedback-list@...adcom.com, devicetree@...r.kernel.org Subject: Re: [PATCH v3 2/3] i2c: iproc: Add Broadcom iProc I2C Driver Hello, On Tue, Jan 13, 2015 at 06:14:17PM -0800, Ray Jui wrote: > >> + irq = platform_get_irq(pdev, 0); > >> + if (irq < 0) { > > irq == 0 should be handled as error, too. > > > Ah. I thought zero is a valid global interrupt number, and I see other > drivers checking against < 0 as well. Is my understanding incorrect? These are wrong, too. 0 should never be a valid interrupt number. There are some exceptions but mostly for historic reasons. The right handling is used for example in drivers/i2c/busses/i2c-efm32.c. > >> + dev_err(dev->device, "no irq resource\n"); > >> + return irq; > >> + } > [...] > >> +static int bcm_iproc_i2c_remove(struct platform_device *pdev) > >> +{ > >> + struct bcm_iproc_i2c_dev *dev = platform_get_drvdata(pdev); > >> + > >> + i2c_del_adapter(&dev->adapter); > >> + bcm_iproc_i2c_disable(dev); > > I think you have a problem here if bcm_iproc_i2c_remove is called while > > an irq is still being serviced. I'm not sure how to prevent this > > properly for a shared interrupt. > > > Can I grab i2c_lock_adapter to ensure the bus is locked (so there's no > outstanding transactions or IRQs by the time we remove the adapter)? But > I see no I2C bus driver does this in their remove function... The problem I pointed out is the reason for some driver authors not to use devm_request_irq. If you use plain request_irq and the matching free_irq in the .remove callback you can be sure that the irq isn't running any more as soon as free_irq returns. BTW, if you use vim, you can add set cinoptions=(,: if has("autocmd") filetype plugin indent on endif to your .vimrc. Then while typing vim does the indention right and consistent, and with the = command you can reindent. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists