Re: kern/55745: spdmem_i2c_match() panics

[SAITOH Masanobu <msaitoh%execsw.org@localhost>]

On 2020/11/17 0:00, Edgar Fuß wrote:
> The following reply was made to PR kern/55745; it has been noted by GNATS.
>
> From: Edgar =?iso-8859-1?B?RnXf?= <ef%math.uni-bonn.de@localhost>
> To: gnats-bugs%netbsd.org@localhost
> Cc: Hauke Fath <hf%spg.tu-darmstadt.de@localhost>
> Subject: Re: kern/55745: spdmem_i2c_match() panics
> Date: Mon, 16 Nov 2020 15:55:19 +0100
>
>   --jq0ap7NbKX2Kqbes
>   Content-Type: text/plain; charset=us-ascii
>   Content-Disposition: inline
>   
>   The problem (at least on -8, didn't check -9) is that sys/dev/pci/piixpm.c 1.52.6.2 installs NULL handlers for ic_{acquire,release}_bus in some cases, but the rest of the I2C code isn't prepared for that. So I guess one needs to install dummy handlers that only acquire/release the i2c mutex.
>   

LGTM.

Those functions are not "dummy" so I think it would be good to name
them as piixpm_i2c_{acquire,release}_bus() or any other better name.


>   With that change, I can boot again.
>   
>   --jq0ap7NbKX2Kqbes
>   Content-Type: text/plain; charset=us-ascii
>   Content-Disposition: attachment; filename="piixpm.c.diff"
>   
>   Index: sys/dev/pci/piixpm.c
>   ===================================================================
>   RCS file: /cvsroot/src/sys/dev/pci/piixpm.c,v
>   retrieving revision 1.52.6.2
>   diff -u -r1.52.6.2 piixpm.c
>   --- sys/dev/pci/piixpm.c	5 Aug 2020 16:11:56 -0000	1.52.6.2
>   +++ sys/dev/pci/piixpm.c	16 Nov 2020 14:35:58 -0000
>   @@ -125,6 +125,8 @@
>    static void	piixpm_csb5_reset(void *);
>    static int	piixpm_i2c_sb800_acquire_bus(void *, int);
>    static void	piixpm_i2c_sb800_release_bus(void *, int);
>   +static int	piixpm_i2c_dummy_acquire_bus(void *, int);
>   +static void	piixpm_i2c_dummy_release_bus(void *, int);
>    static int	piixpm_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *,
>        size_t, void *, size_t, int);
>    
>   @@ -338,8 +340,8 @@
>    			tag->ic_acquire_bus = piixpm_i2c_sb800_acquire_bus;
>    			tag->ic_release_bus = piixpm_i2c_sb800_release_bus;
>    		} else {
>   -			tag->ic_acquire_bus = NULL;
>   -			tag->ic_release_bus = NULL;
>   +			tag->ic_acquire_bus = piixpm_i2c_dummy_acquire_bus;
>   +			tag->ic_release_bus = piixpm_i2c_dummy_release_bus;
>    		}
>    		tag->ic_exec = piixpm_i2c_exec;
>    		memset(&iba, 0, sizeof(iba));
>   @@ -549,6 +551,18 @@
>    	return 0;
>    }
>    
>   +static int
>   +piixpm_i2c_dummy_acquire_bus(void *cookie, int flags)
>   +{
>   +	struct piixpm_smbus *smbus = cookie;
>   +	struct piixpm_softc *sc = smbus->softc;
>   +
>   +	if (!cold)
>   +		mutex_enter(&sc->sc_i2c_mutex);
>   +
>   +	return 0;
>   +}
>   +
>    static void
>    piixpm_i2c_sb800_release_bus(void *cookie, int flags)
>    {
>   @@ -590,6 +604,16 @@
>    		mutex_exit(&sc->sc_i2c_mutex);
>    }
>    
>   +static void
>   +piixpm_i2c_dummy_release_bus(void *cookie, int flags)
>   +{
>   +	struct piixpm_smbus *smbus = cookie;
>   +	struct piixpm_softc *sc = smbus->softc;
>   +
>   +	if (!cold)
>   +		mutex_exit(&sc->sc_i2c_mutex);
>   +}
>   +
>    static int
>    piixpm_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr,
>        const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags)
>   
>   --jq0ap7NbKX2Kqbes--
>   


--
-----------------------------------------------
                SAITOH Masanobu (msaitoh%execsw.org@localhost
                                 msaitoh%netbsd.org@localhost)