Re: [RFC PATCH v6 1/6] x86/uaccess: Allow access_ok() in irq context if pagefault_disabled

2019-05-06 Thread Steven Rostedt
On Tue, 7 May 2019 00:22:03 +0900 Masami Hiramatsu wrote: > Hi Steve, > > It seems I missed this message... No problem. The number of times I missed messages... ugh. > > > > > I'm curious, what interrupt handler are kprobes executing in that needs > > random user space addresses? > >

Re: [RFC PATCH v6 1/6] x86/uaccess: Allow access_ok() in irq context if pagefault_disabled

2019-05-06 Thread Masami Hiramatsu
Hi Steve, It seems I missed this message... On Thu, 21 Mar 2019 22:46:02 -0400 Steven Rostedt wrote: > On Mon, 18 Mar 2019 15:43:17 +0900 > Masami Hiramatsu wrote: > > > WARN_ON_IN_IRQ() assumes that the access_ok() and following > > user memory access can sleep. But this assumption is not >

Re: [RFC PATCH v6 1/6] x86/uaccess: Allow access_ok() in irq context if pagefault_disabled

2019-03-21 Thread Steven Rostedt
On Mon, 18 Mar 2019 15:43:17 +0900 Masami Hiramatsu wrote: > WARN_ON_IN_IRQ() assumes that the access_ok() and following > user memory access can sleep. But this assumption is not > always correct; when the pagefault is disabled, following > memory access will just returns -EFAULT and never

[RFC PATCH v6 1/6] x86/uaccess: Allow access_ok() in irq context if pagefault_disabled

2019-03-18 Thread Masami Hiramatsu
WARN_ON_IN_IRQ() assumes that the access_ok() and following user memory access can sleep. But this assumption is not always correct; when the pagefault is disabled, following memory access will just returns -EFAULT and never sleep. Add pagefault_disabled() check in WARN_ON_ONCE() so that it can