--- /dev/null
+From 18c0b82a3e4501511b08d0e8676fb08ac08734a3 Mon Sep 17 00:00:00 2001
+From: Mitko Haralanov <mitko.haralanov@intel.com>
+Date: Fri, 16 Jan 2015 08:55:27 -0500
+Subject: IB/qib: Do not write EEPROM
+
+From: Mitko Haralanov <mitko.haralanov@intel.com>
+
+commit 18c0b82a3e4501511b08d0e8676fb08ac08734a3 upstream.
+
+This changeset removes all the code that allows the driver to write to
+the EEPROM and update the recorded error counters and power on hours.
+
+These two stats are unused and writing them exposes a timing risk
+which could leave the EEPROM in a bad state preventing further normal
+operation of the HCA.
+
+Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
+Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
+Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
+Signed-off-by: Roland Dreier <roland@purestorage.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/infiniband/hw/qib/qib.h | 9 -
+ drivers/infiniband/hw/qib/qib_eeprom.c | 181 --------------------------------
+ drivers/infiniband/hw/qib/qib_iba6120.c | 2
+ drivers/infiniband/hw/qib/qib_iba7220.c | 2
+ drivers/infiniband/hw/qib/qib_iba7322.c | 2
+ drivers/infiniband/hw/qib/qib_init.c | 1
+ drivers/infiniband/hw/qib/qib_sysfs.c | 24 ----
+ 7 files changed, 1 insertion(+), 220 deletions(-)
+
+--- a/drivers/infiniband/hw/qib/qib.h
++++ b/drivers/infiniband/hw/qib/qib.h
+@@ -1080,12 +1080,6 @@ struct qib_devdata {
+ /* control high-level access to EEPROM */
+ struct mutex eep_lock;
+ uint64_t traffic_wds;
+- /* active time is kept in seconds, but logged in hours */
+- atomic_t active_time;
+- /* Below are nominal shadow of EEPROM, new since last EEPROM update */
+- uint8_t eep_st_errs[QIB_EEP_LOG_CNT];
+- uint8_t eep_st_new_errs[QIB_EEP_LOG_CNT];
+- uint16_t eep_hrs;
+ /*
+ * masks for which bits of errs, hwerrs that cause
+ * each of the counters to increment.
+@@ -1307,8 +1301,7 @@ int qib_twsi_blk_rd(struct qib_devdata *
+ int qib_twsi_blk_wr(struct qib_devdata *dd, int dev, int addr,
+ const void *buffer, int len);
+ void qib_get_eeprom_info(struct qib_devdata *);
+-int qib_update_eeprom_log(struct qib_devdata *dd);
+-void qib_inc_eeprom_err(struct qib_devdata *dd, u32 eidx, u32 incr);
++#define qib_inc_eeprom_err(dd, eidx, incr)
+ void qib_dump_lookup_output_queue(struct qib_devdata *);
+ void qib_force_pio_avail_update(struct qib_devdata *);
+ void qib_clear_symerror_on_linkup(unsigned long opaque);
+--- a/drivers/infiniband/hw/qib/qib_eeprom.c
++++ b/drivers/infiniband/hw/qib/qib_eeprom.c
+@@ -267,190 +267,9 @@ void qib_get_eeprom_info(struct qib_devd
+ "Board SN %s did not pass functional test: %s\n",
+ dd->serial, ifp->if_comment);
+
+- memcpy(&dd->eep_st_errs, &ifp->if_errcntp, QIB_EEP_LOG_CNT);
+- /*
+- * Power-on (actually "active") hours are kept as little-endian value
+- * in EEPROM, but as seconds in a (possibly as small as 24-bit)
+- * atomic_t while running.
+- */
+- atomic_set(&dd->active_time, 0);
+- dd->eep_hrs = ifp->if_powerhour[0] | (ifp->if_powerhour[1] << 8);
+-
+ done:
+ vfree(buf);
+
+ bail:;
+ }
+
+-/**
+- * qib_update_eeprom_log - copy active-time and error counters to eeprom
+- * @dd: the qlogic_ib device
+- *
+- * Although the time is kept as seconds in the qib_devdata struct, it is
+- * rounded to hours for re-write, as we have only 16 bits in EEPROM.
+- * First-cut code reads whole (expected) struct qib_flash, modifies,
+- * re-writes. Future direction: read/write only what we need, assuming
+- * that the EEPROM had to have been "good enough" for driver init, and
+- * if not, we aren't making it worse.
+- *
+- */
+-int qib_update_eeprom_log(struct qib_devdata *dd)
+-{
+- void *buf;
+- struct qib_flash *ifp;
+- int len, hi_water;
+- uint32_t new_time, new_hrs;
+- u8 csum;
+- int ret, idx;
+- unsigned long flags;
+-
+- /* first, check if we actually need to do anything. */
+- ret = 0;
+- for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
+- if (dd->eep_st_new_errs[idx]) {
+- ret = 1;
+- break;
+- }
+- }
+- new_time = atomic_read(&dd->active_time);
+-
+- if (ret == 0 && new_time < 3600)
+- goto bail;
+-
+- /*
+- * The quick-check above determined that there is something worthy
+- * of logging, so get current contents and do a more detailed idea.
+- * read full flash, not just currently used part, since it may have
+- * been written with a newer definition
+- */
+- len = sizeof(struct qib_flash);
+- buf = vmalloc(len);
+- ret = 1;
+- if (!buf) {
+- qib_dev_err(dd,
+- "Couldn't allocate memory to read %u bytes from eeprom for logging\n",
+- len);
+- goto bail;
+- }
+-
+- /* Grab semaphore and read current EEPROM. If we get an
+- * error, let go, but if not, keep it until we finish write.
+- */
+- ret = mutex_lock_interruptible(&dd->eep_lock);
+- if (ret) {
+- qib_dev_err(dd, "Unable to acquire EEPROM for logging\n");
+- goto free_bail;
+- }
+- ret = qib_twsi_blk_rd(dd, dd->twsi_eeprom_dev, 0, buf, len);
+- if (ret) {
+- mutex_unlock(&dd->eep_lock);
+- qib_dev_err(dd, "Unable read EEPROM for logging\n");
+- goto free_bail;
+- }
+- ifp = (struct qib_flash *)buf;
+-
+- csum = flash_csum(ifp, 0);
+- if (csum != ifp->if_csum) {
+- mutex_unlock(&dd->eep_lock);
+- qib_dev_err(dd, "EEPROM cks err (0x%02X, S/B 0x%02X)\n",
+- csum, ifp->if_csum);
+- ret = 1;
+- goto free_bail;
+- }
+- hi_water = 0;
+- spin_lock_irqsave(&dd->eep_st_lock, flags);
+- for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
+- int new_val = dd->eep_st_new_errs[idx];
+- if (new_val) {
+- /*
+- * If we have seen any errors, add to EEPROM values
+- * We need to saturate at 0xFF (255) and we also
+- * would need to adjust the checksum if we were
+- * trying to minimize EEPROM traffic
+- * Note that we add to actual current count in EEPROM,
+- * in case it was altered while we were running.
+- */
+- new_val += ifp->if_errcntp[idx];
+- if (new_val > 0xFF)
+- new_val = 0xFF;
+- if (ifp->if_errcntp[idx] != new_val) {
+- ifp->if_errcntp[idx] = new_val;
+- hi_water = offsetof(struct qib_flash,
+- if_errcntp) + idx;
+- }
+- /*
+- * update our shadow (used to minimize EEPROM
+- * traffic), to match what we are about to write.
+- */
+- dd->eep_st_errs[idx] = new_val;
+- dd->eep_st_new_errs[idx] = 0;
+- }
+- }
+- /*
+- * Now update active-time. We would like to round to the nearest hour
+- * but unless atomic_t are sure to be proper signed ints we cannot,
+- * because we need to account for what we "transfer" to EEPROM and
+- * if we log an hour at 31 minutes, then we would need to set
+- * active_time to -29 to accurately count the _next_ hour.
+- */
+- if (new_time >= 3600) {
+- new_hrs = new_time / 3600;
+- atomic_sub((new_hrs * 3600), &dd->active_time);
+- new_hrs += dd->eep_hrs;
+- if (new_hrs > 0xFFFF)
+- new_hrs = 0xFFFF;
+- dd->eep_hrs = new_hrs;
+- if ((new_hrs & 0xFF) != ifp->if_powerhour[0]) {
+- ifp->if_powerhour[0] = new_hrs & 0xFF;
+- hi_water = offsetof(struct qib_flash, if_powerhour);
+- }
+- if ((new_hrs >> 8) != ifp->if_powerhour[1]) {
+- ifp->if_powerhour[1] = new_hrs >> 8;
+- hi_water = offsetof(struct qib_flash, if_powerhour) + 1;
+- }
+- }
+- /*
+- * There is a tiny possibility that we could somehow fail to write
+- * the EEPROM after updating our shadows, but problems from holding
+- * the spinlock too long are a much bigger issue.
+- */
+- spin_unlock_irqrestore(&dd->eep_st_lock, flags);
+- if (hi_water) {
+- /* we made some change to the data, uopdate cksum and write */
+- csum = flash_csum(ifp, 1);
+- ret = eeprom_write_with_enable(dd, 0, buf, hi_water + 1);
+- }
+- mutex_unlock(&dd->eep_lock);
+- if (ret)
+- qib_dev_err(dd, "Failed updating EEPROM\n");
+-
+-free_bail:
+- vfree(buf);
+-bail:
+- return ret;
+-}
+-
+-/**
+- * qib_inc_eeprom_err - increment one of the four error counters
+- * that are logged to EEPROM.
+- * @dd: the qlogic_ib device
+- * @eidx: 0..3, the counter to increment
+- * @incr: how much to add
+- *
+- * Each counter is 8-bits, and saturates at 255 (0xFF). They
+- * are copied to the EEPROM (aka flash) whenever qib_update_eeprom_log()
+- * is called, but it can only be called in a context that allows sleep.
+- * This function can be called even at interrupt level.
+- */
+-void qib_inc_eeprom_err(struct qib_devdata *dd, u32 eidx, u32 incr)
+-{
+- uint new_val;
+- unsigned long flags;
+-
+- spin_lock_irqsave(&dd->eep_st_lock, flags);
+- new_val = dd->eep_st_new_errs[eidx] + incr;
+- if (new_val > 255)
+- new_val = 255;
+- dd->eep_st_new_errs[eidx] = new_val;
+- spin_unlock_irqrestore(&dd->eep_st_lock, flags);
+-}
+--- a/drivers/infiniband/hw/qib/qib_iba6120.c
++++ b/drivers/infiniband/hw/qib/qib_iba6120.c
+@@ -2682,8 +2682,6 @@ static void qib_get_6120_faststats(unsig
+ spin_lock_irqsave(&dd->eep_st_lock, flags);
+ traffic_wds -= dd->traffic_wds;
+ dd->traffic_wds += traffic_wds;
+- if (traffic_wds >= QIB_TRAFFIC_ACTIVE_THRESHOLD)
+- atomic_add(5, &dd->active_time); /* S/B #define */
+ spin_unlock_irqrestore(&dd->eep_st_lock, flags);
+
+ qib_chk_6120_errormask(dd);
+--- a/drivers/infiniband/hw/qib/qib_iba7220.c
++++ b/drivers/infiniband/hw/qib/qib_iba7220.c
+@@ -3299,8 +3299,6 @@ static void qib_get_7220_faststats(unsig
+ spin_lock_irqsave(&dd->eep_st_lock, flags);
+ traffic_wds -= dd->traffic_wds;
+ dd->traffic_wds += traffic_wds;
+- if (traffic_wds >= QIB_TRAFFIC_ACTIVE_THRESHOLD)
+- atomic_add(5, &dd->active_time); /* S/B #define */
+ spin_unlock_irqrestore(&dd->eep_st_lock, flags);
+ done:
+ mod_timer(&dd->stats_timer, jiffies + HZ * ACTIVITY_TIMER);
+--- a/drivers/infiniband/hw/qib/qib_iba7322.c
++++ b/drivers/infiniband/hw/qib/qib_iba7322.c
+@@ -5191,8 +5191,6 @@ static void qib_get_7322_faststats(unsig
+ spin_lock_irqsave(&ppd->dd->eep_st_lock, flags);
+ traffic_wds -= ppd->dd->traffic_wds;
+ ppd->dd->traffic_wds += traffic_wds;
+- if (traffic_wds >= QIB_TRAFFIC_ACTIVE_THRESHOLD)
+- atomic_add(ACTIVITY_TIMER, &ppd->dd->active_time);
+ spin_unlock_irqrestore(&ppd->dd->eep_st_lock, flags);
+ if (ppd->cpspec->qdr_dfe_on && (ppd->link_speed_active &
+ QIB_IB_QDR) &&
+--- a/drivers/infiniband/hw/qib/qib_init.c
++++ b/drivers/infiniband/hw/qib/qib_init.c
+@@ -922,7 +922,6 @@ static void qib_shutdown_device(struct q
+ }
+ }
+
+- qib_update_eeprom_log(dd);
+ }
+
+ /**
+--- a/drivers/infiniband/hw/qib/qib_sysfs.c
++++ b/drivers/infiniband/hw/qib/qib_sysfs.c
+@@ -611,28 +611,6 @@ bail:
+ return ret < 0 ? ret : count;
+ }
+
+-static ssize_t show_logged_errs(struct device *device,
+- struct device_attribute *attr, char *buf)
+-{
+- struct qib_ibdev *dev =
+- container_of(device, struct qib_ibdev, ibdev.dev);
+- struct qib_devdata *dd = dd_from_dev(dev);
+- int idx, count;
+-
+- /* force consistency with actual EEPROM */
+- if (qib_update_eeprom_log(dd) != 0)
+- return -ENXIO;
+-
+- count = 0;
+- for (idx = 0; idx < QIB_EEP_LOG_CNT; ++idx) {
+- count += scnprintf(buf + count, PAGE_SIZE - count, "%d%c",
+- dd->eep_st_errs[idx],
+- idx == (QIB_EEP_LOG_CNT - 1) ? '\n' : ' ');
+- }
+-
+- return count;
+-}
+-
+ /*
+ * Dump tempsense regs. in decimal, to ease shell-scripts.
+ */
+@@ -679,7 +657,6 @@ static DEVICE_ATTR(nctxts, S_IRUGO, show
+ static DEVICE_ATTR(nfreectxts, S_IRUGO, show_nfreectxts, NULL);
+ static DEVICE_ATTR(serial, S_IRUGO, show_serial, NULL);
+ static DEVICE_ATTR(boardversion, S_IRUGO, show_boardversion, NULL);
+-static DEVICE_ATTR(logged_errors, S_IRUGO, show_logged_errs, NULL);
+ static DEVICE_ATTR(tempsense, S_IRUGO, show_tempsense, NULL);
+ static DEVICE_ATTR(localbus_info, S_IRUGO, show_localbus_info, NULL);
+ static DEVICE_ATTR(chip_reset, S_IWUSR, NULL, store_chip_reset);
+@@ -693,7 +670,6 @@ static struct device_attribute *qib_attr
+ &dev_attr_nfreectxts,
+ &dev_attr_serial,
+ &dev_attr_boardversion,
+- &dev_attr_logged_errors,
+ &dev_attr_tempsense,
+ &dev_attr_localbus_info,
+ &dev_attr_chip_reset,