Commit bba14295 authored by Borislav Petkov's avatar Borislav Petkov
Browse files

EDAC: Correct channel count limit 



c44696ff ("EDAC: Remove arbitrary limit on number of channels")
lifted the arbitrary limit on memory controller channels in EDAC.
However, the dynamic channel attributes dynamic_csrow_dimm_attr and
dynamic_csrow_ce_count_attr remained 6.

This wasn't a problem except channels 6 and 7 weren't visible in sysfs
on machines with more than 6 channels after the conversion to static
attr groups with

  2c1946b6 ("EDAC: Use static attribute groups for managing sysfs entries")

 [ without that, we're exploding in edac_create_sysfs_mci_device()
   because we're dereferencing out of the bounds of the
   dynamic_csrow_dimm_attr array. ]

Add attributes for channels 6 and 7 along with a guard for the
future, should more channels be required and/or to sanity check for
misconfigured machines.

We still need to check against the number of channels present on the MC
first, as Thor reported.

Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reported-by: default avatarHironobu Ishii <ishii.hironobu@jp.fujitsu.com>
Tested-by: default avatarThor Thayer <tthayer@opensource.altera.com>
Cc: <stable@vger.kernel.org> # 4.2
parent 6ba92fea

drivers/edac/edac_mc_sysfs.c

+19 −1
Original line number Diff line number Diff line
@@ -313,7 +313,6 @@ static struct device_type csrow_attr_type = { 
 * possible dynamic channel DIMM Label attribute files

 *

 */



DEVICE_CHANNEL(ch0_dimm_label, S_IRUGO | S_IWUSR,

	channel_dimm_label_show, channel_dimm_label_store, 0);

DEVICE_CHANNEL(ch1_dimm_label, S_IRUGO | S_IWUSR,
@@ -326,6 +325,10 @@ DEVICE_CHANNEL(ch4_dimm_label, S_IRUGO | S_IWUSR, 
	channel_dimm_label_show, channel_dimm_label_store, 4);

DEVICE_CHANNEL(ch5_dimm_label, S_IRUGO | S_IWUSR,

	channel_dimm_label_show, channel_dimm_label_store, 5);

DEVICE_CHANNEL(ch6_dimm_label, S_IRUGO | S_IWUSR,

	channel_dimm_label_show, channel_dimm_label_store, 6);

DEVICE_CHANNEL(ch7_dimm_label, S_IRUGO | S_IWUSR,

	channel_dimm_label_show, channel_dimm_label_store, 7);



/* Total possible dynamic DIMM Label attribute file table */

static struct attribute *dynamic_csrow_dimm_attr[] = {
@@ -335,6 +338,8 @@ static struct attribute *dynamic_csrow_dimm_attr[] = { 
	&dev_attr_legacy_ch3_dimm_label.attr.attr,

	&dev_attr_legacy_ch4_dimm_label.attr.attr,

	&dev_attr_legacy_ch5_dimm_label.attr.attr,

	&dev_attr_legacy_ch6_dimm_label.attr.attr,

	&dev_attr_legacy_ch7_dimm_label.attr.attr,

	NULL

};
@@ -351,6 +356,10 @@ DEVICE_CHANNEL(ch4_ce_count, S_IRUGO, 
		   channel_ce_count_show, NULL, 4);

DEVICE_CHANNEL(ch5_ce_count, S_IRUGO,

		   channel_ce_count_show, NULL, 5);

DEVICE_CHANNEL(ch6_ce_count, S_IRUGO,

		   channel_ce_count_show, NULL, 6);

DEVICE_CHANNEL(ch7_ce_count, S_IRUGO,

		   channel_ce_count_show, NULL, 7);



/* Total possible dynamic ce_count attribute file table */

static struct attribute *dynamic_csrow_ce_count_attr[] = {
@@ -360,6 +369,8 @@ static struct attribute *dynamic_csrow_ce_count_attr[] = { 
	&dev_attr_legacy_ch3_ce_count.attr.attr,

	&dev_attr_legacy_ch4_ce_count.attr.attr,

	&dev_attr_legacy_ch5_ce_count.attr.attr,

	&dev_attr_legacy_ch6_ce_count.attr.attr,

	&dev_attr_legacy_ch7_ce_count.attr.attr,

	NULL

};
@@ -371,9 +382,16 @@ static umode_t csrow_dev_is_visible(struct kobject *kobj, 


	if (idx >= csrow->nr_channels)

		return 0;



	if (idx >= ARRAY_SIZE(dynamic_csrow_ce_count_attr) - 1) {

		WARN_ONCE(1, "idx: %d\n", idx);

		return 0;

	}



	/* Only expose populated DIMMs */

	if (!csrow->channels[idx]->dimm->nr_pages)

		return 0;



	return attr->mode;

}

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