Re: Peculiar out-of-sync boot log lines

From: Bartlomiej Zolnierkiewicz
Date: Sat Dec 01 2007 - 17:45:33 EST



Hi,

On Thursday 29 November 2007, Mark Lord wrote:
> Nick Warne wrote:
> > Hi all,
> >
> > 2.6.23.9
> >
> > I have noticed after applying Bart's patch to word93 blacklist my new
> > DVD drive:
> >
> > http://lkml.org/lkml/2007/10/23/475
> >
> > I see now in logs (look at the hdd line:
> >
> > [dmesg]
> > hdc: 39876480 sectors (20416 MB) w/2048KiB Cache, CHS=39560/16/63,
> > UDMA(66)
> > hdc: cache flushes not supported
> > hdc: hdc1
> > hdd: ATAPI 48X DVD-ROM DVD-R-RAM CD-R/RW drive, 2048kB Cache<7>hdd:
> > skipping word 93 validity check
> > , UDMA(66)
> > Uniform CD-ROM driver Revision: 3.20
> >
> >
> > <7> ?? And the ", UDMA(66)" gets new lined, so in syslog it appears all
> > by itself:
> ...
>
> That's a minor bug with the patch.
>
> The code does this:
>
> ide_dma_verbose::printk( ... "2048kB Cache");
> eighty_ninty_three::printk(KERN_DEBUG "%s: skipping word 93 validity check\n");
> ide_dma_verbose::printk(", UDMA(66)"

Thanks for reporting/debugging it guys!

> Something in there needs to insert a '\n' before the "skipping word" message.
> Since it doesn't do that right now, the KERN_DEBUG string appears as "<7>"

This seems like a good occasion to fix ide_dma_verbose() for good so... :)

[ patch is against current Linus tree so might not apply to 2.6.23.9 ]

[PATCH] ide: DMA reporting and validity checking fixes

* ide_xfer_verbose() fixups:
- beautify returned mode names
- fix PIO5 reporting
- make it return 'const char *'

* Change printk() level from KERN_DEBUG to KERN_INFO in ide_find_dma_mode().

* Add ide_id_dma_bug() helper based on ide_dma_verbose() to check for invalid
DMA info in identify block.

* Use ide_id_dma_bug() in ide_tune_dma() and ide_driveid_update().

As a result DMA won't be tuned or will be disabled after tuning if device
reports inconsistent info about enabled DMA mode (ide_dma_verbose() does the
same checks while the IDE device is probed by ide-{cd,disk} device driver).

* Since (id->capability & 1) && id->tDMA is a valid configuration handle
it correctly in ide_id_dma_bug().

* Remove no longer needed ide_dma_verbose().

This patch should fix the following problem with out-of-sync IDE messages
reported by Nick Warned:

hdd: ATAPI 48X DVD-ROM DVD-R-RAM CD-R/RW drive, 2048kB Cache<7>hdd:
skipping word 93 validity check
, UDMA(66)

and later debugged by Mark Lord to be caused by:

ide_dma_verbose()
printk( ... "2048kB Cache");
eighty_ninty_three()
printk(KERN_DEBUG "%s: skipping word 93 validity check\n");
ide_dma_verbose()
printk(", UDMA(66)"

Please note that as a result ide-{cd,disk} device drivers won't report the
DMA speed used but this is intended since now DMA mode being used is always
reported by IDE core code.

Cc: Nick Warne <nick@xxxxxxxxx>
Cc: Mark Lord <lkml@xxxxxx>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>
---
drivers/ide/ide-cd.c | 7 ------
drivers/ide/ide-disk.c | 5 ----
drivers/ide/ide-dma.c | 57 ++++++++++++-------------------------------------
drivers/ide/ide-iops.c | 3 ++
drivers/ide/ide-lib.c | 55 ++++++++++++++++++++++++-----------------------
include/linux/ide.h | 6 ++---
6 files changed, 51 insertions(+), 82 deletions(-)

Index: b/drivers/ide/ide-cd.c
===================================================================
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -3049,12 +3049,7 @@ int ide_cdrom_probe_capabilities (ide_dr
else
printk(" drive");

- printk(", %dkB Cache", be16_to_cpu(cap.buffer_size));
-
- if (drive->using_dma)
- ide_dma_verbose(drive);
-
- printk("\n");
+ printk(", %dkB Cache\n", be16_to_cpu(cap.buffer_size));

return nslots;
}
Index: b/drivers/ide/ide-disk.c
===================================================================
--- a/drivers/ide/ide-disk.c
+++ b/drivers/ide/ide-disk.c
@@ -961,11 +961,8 @@ static void idedisk_setup (ide_drive_t *
if (id->buf_size)
printk (" w/%dKiB Cache", id->buf_size/2);

- printk(", CHS=%d/%d/%d",
+ printk(", CHS=%d/%d/%d\n",
drive->bios_cyl, drive->bios_head, drive->bios_sect);
- if (drive->using_dma)
- ide_dma_verbose(drive);
- printk("\n");

/* write cache enabled? */
if ((id->csfo & 1) || (id->cfs_enable_1 & (1 << 5)))
Index: b/drivers/ide/ide-dma.c
===================================================================
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -753,7 +753,7 @@ u8 ide_find_dma_mode(ide_drive_t *drive,
mode = XFER_MW_DMA_1;
}

- printk(KERN_DEBUG "%s: %s mode selected\n", drive->name,
+ printk(KERN_INFO "%s: %s mode selected\n", drive->name,
mode ? ide_xfer_verbose(mode) : "no DMA");

return min(mode, req_mode);
@@ -772,6 +772,9 @@ static int ide_tune_dma(ide_drive_t *dri
if (__ide_dma_bad_drive(drive))
return 0;

+ if (ide_id_dma_bug(drive))
+ return 0;
+
if (drive->hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA)
return config_drive_for_dma(drive);

@@ -806,58 +809,26 @@ static int ide_dma_check(ide_drive_t *dr
return vdma ? 0 : -1;
}

-void ide_dma_verbose(ide_drive_t *drive)
+int ide_id_dma_bug(ide_drive_t *drive)
{
- struct hd_driveid *id = drive->id;
- ide_hwif_t *hwif = HWIF(drive);
+ struct hd_driveid *id = drive->id;

if (id->field_valid & 4) {
if ((id->dma_ultra >> 8) && (id->dma_mword >> 8))
- goto bug_dma_off;
- if (id->dma_ultra & ((id->dma_ultra >> 8) & hwif->ultra_mask)) {
- if (((id->dma_ultra >> 11) & 0x1F) &&
- eighty_ninty_three(drive)) {
- if ((id->dma_ultra >> 15) & 1) {
- printk(", UDMA(mode 7)");
- } else if ((id->dma_ultra >> 14) & 1) {
- printk(", UDMA(133)");
- } else if ((id->dma_ultra >> 13) & 1) {
- printk(", UDMA(100)");
- } else if ((id->dma_ultra >> 12) & 1) {
- printk(", UDMA(66)");
- } else if ((id->dma_ultra >> 11) & 1) {
- printk(", UDMA(44)");
- } else
- goto mode_two;
- } else {
- mode_two:
- if ((id->dma_ultra >> 10) & 1) {
- printk(", UDMA(33)");
- } else if ((id->dma_ultra >> 9) & 1) {
- printk(", UDMA(25)");
- } else if ((id->dma_ultra >> 8) & 1) {
- printk(", UDMA(16)");
- }
- }
- } else {
- printk(", (U)DMA"); /* Can be BIOS-enabled! */
- }
+ goto err_out;
} else if (id->field_valid & 2) {
if ((id->dma_mword >> 8) && (id->dma_1word >> 8))
- goto bug_dma_off;
- printk(", DMA");
+ goto err_out;
} else if (id->field_valid & 1) {
- goto bug_dma_off;
+ if (id->tDMA == 0)
+ goto err_out;
}
- return;
-bug_dma_off:
- printk(", BUG DMA OFF");
- hwif->dma_off_quietly(drive);
- return;
+ return 0;
+err_out:
+ printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
+ return 1;
}

-EXPORT_SYMBOL(ide_dma_verbose);
-
int ide_set_dma(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
Index: b/drivers/ide/ide-iops.c
===================================================================
--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -748,6 +748,9 @@ int ide_driveid_update(ide_drive_t *driv
drive->id->dma_1word = id->dma_1word;
/* anything more ? */
kfree(id);
+
+ if (drive->using_dma && ide_id_dma_bug(drive))
+ ide_dma_off(drive);
}

return 1;
Index: b/drivers/ide/ide-lib.c
===================================================================
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -29,41 +29,44 @@
* Add common non I/O op stuff here. Make sure it has proper
* kernel-doc function headers or your patch will be rejected
*/
-
+
+static const char *udma_str[] =
+ { "UDMA/16", "UDMA/25", "UDMA/33", "UDMA/44",
+ "UDMA/66", "UDMA/100", "UDMA/133", "UDMA7" };
+static const char *mwdma_str[] =
+ { "MWDMA0", "MWDMA1", "MWDMA2" };
+static const char *swdma_str[] =
+ { "SWDMA0", "SWDMA1", "SWDMA2" };
+static const char *pio_str[] =
+ { "PIO0", "PIO1", "PIO2", "PIO3", "PIO4", "PIO5" };

/**
* ide_xfer_verbose - return IDE mode names
- * @xfer_rate: rate to name
+ * @mode: transfer mode
*
* Returns a constant string giving the name of the mode
* requested.
*/

-char *ide_xfer_verbose (u8 xfer_rate)
+const char *ide_xfer_verbose(u8 mode)
{
- switch(xfer_rate) {
- case XFER_UDMA_7: return("UDMA 7");
- case XFER_UDMA_6: return("UDMA 6");
- case XFER_UDMA_5: return("UDMA 5");
- case XFER_UDMA_4: return("UDMA 4");
- case XFER_UDMA_3: return("UDMA 3");
- case XFER_UDMA_2: return("UDMA 2");
- case XFER_UDMA_1: return("UDMA 1");
- case XFER_UDMA_0: return("UDMA 0");
- case XFER_MW_DMA_2: return("MW DMA 2");
- case XFER_MW_DMA_1: return("MW DMA 1");
- case XFER_MW_DMA_0: return("MW DMA 0");
- case XFER_SW_DMA_2: return("SW DMA 2");
- case XFER_SW_DMA_1: return("SW DMA 1");
- case XFER_SW_DMA_0: return("SW DMA 0");
- case XFER_PIO_4: return("PIO 4");
- case XFER_PIO_3: return("PIO 3");
- case XFER_PIO_2: return("PIO 2");
- case XFER_PIO_1: return("PIO 1");
- case XFER_PIO_0: return("PIO 0");
- case XFER_PIO_SLOW: return("PIO SLOW");
- default: return("XFER ERROR");
- }
+ const char *s;
+ u8 i = mode & 0xf;
+
+ if (mode >= XFER_UDMA_0 && mode <= XFER_UDMA_7)
+ s = udma_str[i];
+ else if (mode >= XFER_MW_DMA_0 && mode <= XFER_MW_DMA_2)
+ s = mwdma_str[i];
+ else if (mode >= XFER_SW_DMA_0 && mode <= XFER_SW_DMA_2)
+ s = swdma_str[i];
+ else if (mode >= XFER_PIO_0 && mode <= XFER_PIO_5)
+ s = pio_str[i & 0x7];
+ else if (mode == XFER_PIO_SLOW)
+ s = "XFER SLOW";
+ else
+ s = "XFER ERROR";
+
+ return s;
}

EXPORT_SYMBOL(ide_xfer_verbose);
Index: b/include/linux/ide.h
===================================================================
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -1255,6 +1255,7 @@ int ide_in_drive_list(struct hd_driveid

#ifdef CONFIG_BLK_DEV_IDEDMA
int __ide_dma_bad_drive(ide_drive_t *);
+int ide_id_dma_bug(ide_drive_t *);

u8 ide_find_dma_mode(ide_drive_t *, u8);

@@ -1264,7 +1265,6 @@ static inline u8 ide_max_dma_mode(ide_dr
}

void ide_dma_off(ide_drive_t *);
-void ide_dma_verbose(ide_drive_t *);
int ide_set_dma(ide_drive_t *);
ide_startstop_t ide_dma_intr(ide_drive_t *);

@@ -1287,6 +1287,7 @@ extern void ide_dma_timeout(ide_drive_t
#endif /* CONFIG_BLK_DEV_IDEDMA_PCI */

#else
+static inline int ide_id_dma_bug(ide_drive_t *drive) { return 0; }
static inline u8 ide_find_dma_mode(ide_drive_t *drive, u8 speed) { return 0; }
static inline u8 ide_max_dma_mode(ide_drive_t *drive) { return 0; }
static inline void ide_dma_off(ide_drive_t *drive) { ; }
@@ -1333,8 +1334,7 @@ static inline void ide_set_hwifdata (ide
hwif->hwif_data = data;
}

-/* ide-lib.c */
-extern char *ide_xfer_verbose(u8 xfer_rate);
+const char *ide_xfer_verbose(u8);
extern void ide_toggle_bounce(ide_drive_t *drive, int on);
extern int ide_set_xfer_rate(ide_drive_t *drive, u8 rate);

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