From f0de53bbc2118c754ee923516122d91add288582 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sat, 16 Apr 2005 15:25:10 -0700 Subject: [PATCH] [PATCH] x86_64: Remove excessive stack allocation in MCE code with large NR_CPUS Remove excessive stack allocation in MCE code with large NR_CPUS Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86_64/kernel/mce.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86_64/kernel/mce.c b/arch/x86_64/kernel/mce.c index 6ca066424d..3a89d735a4 100644 --- a/arch/x86_64/kernel/mce.c +++ b/arch/x86_64/kernel/mce.c @@ -379,18 +379,23 @@ static void collect_tscs(void *data) static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize, loff_t *off) { - unsigned long cpu_tsc[NR_CPUS]; + unsigned long *cpu_tsc; static DECLARE_MUTEX(mce_read_sem); unsigned next; char __user *buf = ubuf; int i, err; + cpu_tsc = kmalloc(NR_CPUS * sizeof(long), GFP_KERNEL); + if (!cpu_tsc) + return -ENOMEM; + down(&mce_read_sem); next = rcu_dereference(mcelog.next); /* Only supports full reads right now */ if (*off != 0 || usize < MCE_LOG_LEN*sizeof(struct mce)) { up(&mce_read_sem); + kfree(cpu_tsc); return -EINVAL; } @@ -421,6 +426,7 @@ static ssize_t mce_read(struct file *filp, char __user *ubuf, size_t usize, loff } } up(&mce_read_sem); + kfree(cpu_tsc); return err ? -EFAULT : buf - ubuf; } -- 2.39.5