Messages in this thread | | | Date | Mon, 8 Oct 2012 11:24:13 +0100 | From | Dave Martin <> | Subject | Re: [PATCH] [ARM] Use AT() in the linker script to create correct program headers |
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On Fri, Oct 05, 2012 at 09:45:00AM +0100, Russell King - ARM Linux wrote: > On Mon, Oct 01, 2012 at 10:06:39AM -0600, Jason Gunthorpe wrote: > > On Mon, Oct 01, 2012 at 04:39:53PM +0100, Dave Martin wrote: > > > > Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align > > > > LOAD 0x008000 0xc0008000 0x00008000 0x372244 0x3a4310 RWE 0x8000 > > > > > > Not related directly to your patch, but I wonder why we don't we see > > > separate r-x and rw- segments? > > > > I think this is because the sections are not aligned when the > > protections change, and the sections are not sorted by protection > > type. > > They aren't sorted by protection type, they're ordered according to what's > required for the kernel - which is to have the init sections together as > one complete block so that it can be freed, and to place all of the kernel > text as close to the beginning of the image as possible.
Ah, right.
Partly this came from some side speculation about whether we could do things like privileged read-only permissions on newer CPUs, for preventing unintended or undesired writes to the kernel's code or read-only data.
There would be various things to solve in order to make that work, so I guess there's no great urgency for it right now.
Cheers ---Dave
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