linux-kernel - [PATCH] Fix unlock ordering in smp

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Thu, 03 Apr 2008 14:30:36 -0400
From:	"Alan D. Brunelle" <Alan.Brunelle@...com>
To:	linux-ia64@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, tony.luck@...el.com
Subject: [PATCH] Fix unlock ordering in smp_callin

One should normally unlock in the reverse order of the lock calls,
and in this case there certainly is no reason not to.

To better see the results (with locks included), here's the complete
section of corrected code:

        lock_ipi_calllock();
        spin_lock(&vector_lock);
        /* Setup the per cpu irq handling data structures */
        __setup_vector_irq(cpuid);
        cpu_set(cpuid, cpu_online_map);
        per_cpu(cpu_state, cpuid) = CPU_ONLINE;
        spin_unlock(&vector_lock);
        unlock_ipi_calllock();

Signed-off-by: Alan D. Brunelle <alan.brunelle@...com>
---
 arch/ia64/kernel/smpboot.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/ia64/kernel/smpboot.c b/arch/ia64/kernel/smpboot.c
index 32ee597..16483be 100644
--- a/arch/ia64/kernel/smpboot.c
+++ b/arch/ia64/kernel/smpboot.c
@@ -400,9 +400,9 @@ smp_callin (void)
 	/* Setup the per cpu irq handling data structures */
 	__setup_vector_irq(cpuid);
 	cpu_set(cpuid, cpu_online_map);
-	unlock_ipi_calllock();
 	per_cpu(cpu_state, cpuid) = CPU_ONLINE;
 	spin_unlock(&vector_lock);
+	unlock_ipi_calllock();

 	smp_setup_percpu_timer();

-- 
1.5.2.5


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/