Jon, Ulf, Can we first get the current implementation upstream and _then_ add more patches to it? On Mon, Sep 21, 2015 at 4:19 AM, Jon Hunter <jonathanh@xxxxxxxxxx> wrote: ... >>>> + for (i = 0; i < num_of_cmds; i++) { >>>> + err = __mmc_blk_ioctl_cmd(card, md, idata[i]); >>>> + if (err) { >>>> + mmc_put_card(card); >>>> + goto cmd_done; >>> Instead of exiting here, you should first copy to the user the data >>> and response of successful commands, mark the failed command as failed >>> and the remaining ones as "not executed". >>> This way, it will be easier for the user space application to find out >>> where the sequence failed. This especially true if some reverts are >>> needed. >> >> Yes that sounds like a sensible thing to do. I will incorporate that change. I also liked Gwendal's idea and incorporated that into our 3.18 kernel tree here: https://chromium-review.googlesource.com/#/c/299956 (this is on top of Jon's most recently proposed patch - we'll align with what lands shortly) But as I've demonstrated, this can be a separate patch. cheers, grant > > At first, I thought that may be the response field of the command could > be used to indicate the failed command. However, thinking about this > some more, I am not sure that it seems correct to use this field as this > is really used to carry the MMC response as defined by the MMC > specification. > > Should the response field always be non-zero for a successful command? > If this is guaranteed, then may be the best thing to do would be to have > user-space clear the response field to field before submitting the > commands. It would then be easy to detect which command failed and which > were not attempted. > > Ulf, what are your thoughts? > > Cheers > Jon -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html