linux-kernel - [PATCH 2/5] powernv:idle: Change return type of pnv_probe_idle

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed,  5 Jul 2017 22:08:13 +0530
From:   "Gautham R. Shenoy" <ego@...ux.vnet.ibm.com>
To:     Michael Ellerman <mpe@...erman.id.au>,
        Michael Neuling <mikey@...ling.org>,
        Nicholas Piggin <npiggin@...il.com>,
        Vaidyanathan Srinivasan <svaidy@...ux.vnet.ibm.com>,
        Shilpasri G Bhat <shilpa.bhat@...ux.vnet.ibm.com>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Akshay Adiga <akshay.adiga@...ux.vnet.ibm.com>
Cc:     linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
        linux-pm@...r.kernel.org,
        "Gautham R. Shenoy" <ego@...ux.vnet.ibm.com>
Subject: [PATCH 2/5] powernv:idle: Change return type of pnv_probe_idle_states to int

From: "Gautham R. Shenoy" <ego@...ux.vnet.ibm.com>

In the current idle initialization code, if there are failures in
pnv_probe_idle_states, then no platform idle state is
enabled. However, since the error is not propagated to the top-level
function pnv_init_idle_states, we continue initialization in this
top-level function even though this will never be used.

Hence change the the return type of pnv_probe_idle_states from void to
int and in case of failures, bail out early on in
pnv_init_idle_states.

Signed-off-by: Gautham R. Shenoy <ego@...ux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/idle.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index b747bb5..a5990d9 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -813,26 +813,27 @@ static int __init pnv_idle_parse(struct  device_node *np, int dt_idle_states)
 /*
  * Probe device tree for supported idle states
  */
-static void __init pnv_probe_idle_states(void)
+static int __init pnv_probe_idle_states(void)
 {
 	struct device_node *np;
 	int dt_idle_states;
-	int i;
+	int i, rc;
 
 	np = of_find_node_by_path("/ibm,opal/power-mgt");
 	if (!np) {
 		pr_warn("opal: PowerMgmt Node not found\n");
-		return;
+		return -ENODEV;
 	}
 	dt_idle_states = of_property_count_u32_elems(np,
 			"ibm,cpu-idle-state-flags");
 	if (dt_idle_states < 0) {
 		pr_warn("cpuidle-powernv: no idle states found in the DT\n");
-		return;
+		return -ENOENT;
 	}
 
-	if (pnv_idle_parse(np, dt_idle_states))
-		return;
+	rc = pnv_idle_parse(np, dt_idle_states);
+	if (rc)
+		return rc;
 
 	if (cpu_has_feature(CPU_FTR_ARCH_300))
 		pnv_power9_idle_init();
@@ -842,6 +843,8 @@ static void __init pnv_probe_idle_states(void)
 			continue;
 		supported_cpuidle_states |= pnv_idle.states[i].flags;
 	}
+
+	return 0;
 }
 
 static int __init pnv_init_idle_states(void)
@@ -852,7 +855,8 @@ static int __init pnv_init_idle_states(void)
 	if (cpuidle_disable != IDLE_NO_OVERRIDE)
 		goto out;
 
-	pnv_probe_idle_states();
+	if (pnv_probe_idle_states())
+		goto out;
 
 	if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
 		patch_instruction(
-- 
1.9.4