Re: [RESEND] Cross Memory Attach v3
From: Christopher Yeoh <hidden>
Date: 2011-07-18 15:05:20
On Fri, 15 Jul 2011 15:37:43 -0700 Andrew Morton [off-list ref] wrote:
On Fri, 8 Jul 2011 18:06:07 +0930 Christopher Yeoh [off-list ref] wrote:quoted
+static ssize_t process_vm_rw(pid_t pid, const struct iovec *lvec, + unsigned long liovcnt, + const struct iovec *rvec, + unsigned long riovcnt, + unsigned long flags, int vm_write) +{ ... + if (!mm || (task->flags & PF_KTHREAD)) {Can a PF_KTHREAD thread have a non-zero ->mm?quoted
+ task_unlock(task); + rc = -EINVAL; + goto put_task_struct; + }
According to get_task_mm it can: /** * get_task_mm - acquire a reference to the task's mm * * Returns %NULL if the task has no mm. Checks PF_KTHREAD (meaning * this kernel workthread has transiently adopted a user mm with use_mm, * to do its AIO) is not set and if so returns a reference to it, after * bumping up the use count. User must release the mm via mmput() * after use. Typically used by /proc and ptrace. */
anyway, grumble. Please resend, cc'ing linux-kernel.
Am doing the CC resends in a separate email... Chris -- cyeoh@au.ibm.com -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>