linux-kernel - Re: [PATCH v2 1/2] i2c: smbus: add core function handling SMBus host-notify

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Sun, 2 Aug 2020 21:15:23 +0200
From:   Wolfram Sang <wsa@...nel.org>
To:     "linux-i2c@...r.kernel.org" <linux-i2c@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Cc:     Pierre Yves MORDRET <pierre-yves.mordret@...com>,
        Alexandre TORGUE <alexandre.torgue@...com>,
        "linux-stm32@...md-mailman.stormreply.com" 
        <linux-stm32@...md-mailman.stormreply.com>,
        Fabrice GASNIER <fabrice.gasnier@...com>
Subject: Re: [PATCH v2 1/2] i2c: smbus: add core function handling SMBus
 host-notify

> I've simplified the index handling as you suggested. The only impact is that
> finally we do not consider anymore the I2C_SLAVE_WRITE_REQUESTED event as the
> beginning of the transaction since we don't perform the "reset" of the
> handling upon this event.

One more comment on this one because I had to update the testunit, too.
To be robust against multiple write messages in one transfer, we need to
reset both, after STOP and when I2C_SLAVE_WRITE_REQUESTED. See here:

 96         case I2C_SLAVE_STOP:
 97                 if (tu->reg_idx == TU_NUM_REGS)
 98                         queue_delayed_work(system_long_wq, &tu->worker,
 99                                            msecs_to_jiffies(100 * tu->regs[TU_REG_DELAY]));
100                 fallthrough;
101 
102         case I2C_SLAVE_WRITE_REQUESTED:
103                 tu->reg_idx = 0;
104                 break;

As you see, I used 'fallthrough' to avoid code duplication and that only
one reset part will be updated.

Dunno if you really need it, too, as I haven't seen your latest code yet.


Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)