From b763ec17ac762470eec5be8ebcc43e4f8b2c2b82 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Sat, 19 Sep 2015 07:00:18 -0700 Subject: regmap: debugfs: Ensure we don't underflow when printing access masks If a read is attempted which is smaller than the line length then we may underflow the subtraction we're doing with the unsigned size_t type so move some of the calculation to be additions on the right hand side instead in order to avoid this. Reported-by: Rasmus Villemoes Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/base/regmap/regmap-debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index f42f2bac6466..1f327898e53d 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -432,7 +432,7 @@ static ssize_t regmap_access_read_file(struct file *file, /* If we're in the region the user is trying to read */ if (p >= *ppos) { /* ...but not beyond it */ - if (buf_pos >= count - 1 - tot_len) + if (buf_pos + tot_len + 1 >= count) break; /* Format the register */ -- cgit v1.2.3 From 176fc2d5770a0990eebff903ba680d2edd32e718 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Sat, 19 Sep 2015 07:12:34 -0700 Subject: regmap: debugfs: Don't bother actually printing when calculating max length The in kernel snprintf() will conveniently return the actual length of the printed string even if not given an output beffer at all so just do that rather than relying on the user to pass in a suitable buffer, ensuring that we don't need to worry if the buffer was truncated due to the size of the buffer passed in. Reported-by: Rasmus Villemoes Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/base/regmap/regmap-debugfs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 1f327898e53d..4c55cfbad19e 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -32,8 +32,7 @@ static DEFINE_MUTEX(regmap_debugfs_early_lock); /* Calculate the length of a fixed format */ static size_t regmap_calc_reg_len(int max_val, char *buf, size_t buf_size) { - snprintf(buf, buf_size, "%x", max_val); - return strlen(buf); + return snprintf(NULL, 0, "%x", max_val); } static ssize_t regmap_name_read_file(struct file *file, -- cgit v1.2.3 From a98f1b78ecf325bf29c9d3d1eb38cbc9340000af Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Tue, 13 Oct 2015 16:10:28 +0200 Subject: PM / Domains: Fix validation of latency constraints in genpd governor Commit ba2bbfbf6307 (PM / Domains: Remove intermediate states from the power off sequence) changed the power off sequence in genpd. That also required some updates regarding the validation of latency constraints in the genpd governor. Unfortunate that wasn't covered, so let's fix this. From a runtime PM and latency point of view, we need to consider the worst case scenario while validating latency constraints. That's typically when a call to pm_runtime_get_sync() needs to wait for a ongoing runtime suspend operation to be carried out, as it then also needs to wait for the device to be runtime resumed again. The above mentioned commit made the genpd governor's ->stop_ok() callback responsible of validating genpd's device's runtime suspend/resume latency. In other words, the constraint needs to be validated towards the relevant latencies present in genpd's ->runtime_suspend|resume() callbacks. Earlier, that included latencies from the ->stop|start() callbacks, but as ->save|restore_state() are now also being invoked from genpd's ->runtime_suspend|resume() and to comply with the worst case scenario, let's take also those latencies into account. Fixes: ba2bbfbf6307 (PM / Domains: Remove intermediate states from the power off sequence) Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain_governor.c | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c index 2a4154a09e4d..85e17bacc834 100644 --- a/drivers/base/power/domain_governor.c +++ b/drivers/base/power/domain_governor.c @@ -77,13 +77,16 @@ static bool default_stop_ok(struct device *dev) dev_update_qos_constraint); if (constraint_ns > 0) { - constraint_ns -= td->start_latency_ns; + constraint_ns -= td->save_state_latency_ns + + td->stop_latency_ns + + td->start_latency_ns + + td->restore_state_latency_ns; if (constraint_ns == 0) return false; } td->effective_constraint_ns = constraint_ns; - td->cached_stop_ok = constraint_ns > td->stop_latency_ns || - constraint_ns == 0; + td->cached_stop_ok = constraint_ns >= 0; + /* * The children have been suspended already, so we don't need to take * their stop latencies into account here. @@ -126,18 +129,6 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) off_on_time_ns = genpd->power_off_latency_ns + genpd->power_on_latency_ns; - /* - * It doesn't make sense to remove power from the domain if saving - * the state of all devices in it and the power off/power on operations - * take too much time. - * - * All devices in this domain have been stopped already at this point. - */ - list_for_each_entry(pdd, &genpd->dev_list, list_node) { - if (pdd->dev->driver) - off_on_time_ns += - to_gpd_data(pdd)->td.save_state_latency_ns; - } min_off_time_ns = -1; /* @@ -193,7 +184,6 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) * constraint_ns cannot be negative here, because the device has * been suspended. */ - constraint_ns -= td->restore_state_latency_ns; if (constraint_ns <= off_on_time_ns) return false; -- cgit v1.2.3