On Wed, Oct 16, 2024 at 03:24:20PM +0300, Mike Rapoport wrote: > From: "Mike Rapoport (Microsoft)" <rppt@xxxxxxxxxx> > > In order to support ROX allocations for module text, it is necessary to > handle modifications to the code, such as relocations and alternatives > patching, without write access to that memory. > > One option is to use text patching, but this would make module loading > extremely slow and will expose executable code that is not finally formed. > > A better way is to have memory allocated with ROX permissions contain > invalid instructions and keep a writable, but not executable copy of the > module text. The relocations and alternative patches would be done on the > writable copy using the addresses of the ROX memory. > Once the module is completely ready, the updated text will be copied to ROX > memory using text patching in one go and the writable copy will be freed. > > Add support for that to module initialization code and provide necessary > interfaces in execmem. > > Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx> Reviewd-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> Luis
