mmc: sdhci: fix NULL dereference in sdhci_request() tuning

Commit 473b095a72 ("mmc: sdhci: fix incorrect command used in tuning")
introduced a NULL dereference at resume-time if an SD 3.0 host controller
raises the SDHCI_NEEDS_TUNING flag while no card is inserted.  Seen on an
OLPC XO-4 with sdhci-pxav3, but presumably affects other controllers too.

Signed-off-by: Chris Ball <cjb@laptop.org>
Cc: stable <stable@vger.kernel.org> [3.3+]
This commit is contained in:
Chris Ball 2012-11-05 14:29:49 -05:00
Родитель 657d59823c
Коммит 14efd95720
1 изменённых файлов: 12 добавлений и 9 удалений

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@ -1315,16 +1315,19 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
*/ */
if ((host->flags & SDHCI_NEEDS_RETUNING) && if ((host->flags & SDHCI_NEEDS_RETUNING) &&
!(present_state & (SDHCI_DOING_WRITE | SDHCI_DOING_READ))) { !(present_state & (SDHCI_DOING_WRITE | SDHCI_DOING_READ))) {
/* eMMC uses cmd21 while sd and sdio use cmd19 */ if (mmc->card) {
tuning_opcode = mmc->card->type == MMC_TYPE_MMC ? /* eMMC uses cmd21 but sd and sdio use cmd19 */
MMC_SEND_TUNING_BLOCK_HS200 : tuning_opcode =
MMC_SEND_TUNING_BLOCK; mmc->card->type == MMC_TYPE_MMC ?
spin_unlock_irqrestore(&host->lock, flags); MMC_SEND_TUNING_BLOCK_HS200 :
sdhci_execute_tuning(mmc, tuning_opcode); MMC_SEND_TUNING_BLOCK;
spin_lock_irqsave(&host->lock, flags); spin_unlock_irqrestore(&host->lock, flags);
sdhci_execute_tuning(mmc, tuning_opcode);
spin_lock_irqsave(&host->lock, flags);
/* Restore original mmc_request structure */ /* Restore original mmc_request structure */
host->mrq = mrq; host->mrq = mrq;
}
} }
if (mrq->sbc && !(host->flags & SDHCI_AUTO_CMD23)) if (mrq->sbc && !(host->flags & SDHCI_AUTO_CMD23))