On Thu, Aug 13, 2020 at 04:19:27PM +0000, David Laight wrote: > From: Josef Bacik > > Sent: 13 August 2020 15:53 > > > > sysctl: pass kernel pointers to ->proc_handler > > > > we have been pre-allocating a buffer to copy the data from the proc > > handlers into, and then copying that to userspace. The problem is this > > just blind kmalloc()'s the buffer size passed in from the read, which in > > the case of our 'cat' binary was 64kib. Order-4 allocations are not > > awesome, and since we can potentially allocate up to our maximum order, > > use vmalloc for these buffers. > > What happens if I run 'dd bs=16M ...' ? Try it.
