Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-01 Thread Stanislav Kozina
On 12/01/2016 05:13 AM, Don Zickus wrote: ... I think GregKH pointed to one such tool, libabigail? We are working on others too. I should mention one of the others here: https://github.com/skozina/kabi-dw It's quite comparable to libabigail in the way it works, the main differences are:

Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-01 Thread Stanislav Kozina
On 12/01/2016 12:09 PM, Nicholas Piggin wrote: On Thu, 1 Dec 2016 11:48:09 +0100 Stanislav Kozina wrote: On 12/01/2016 05:13 AM, Don Zickus wrote: ... I think GregKH pointed to one such tool, libabigail? We are working on others too. I should mention one of the others here: https

Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-09 Thread Stanislav Kozina
The question is how to provide a similar guarantee if a different way? As a tool to aid distro reviewers, modversions has some value, but the debug info parsing tools that have been mentioned in this thread seem superior (not that I've tested them). On the other hand the big advantage of modver

Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-09 Thread Stanislav Kozina
The question is how to provide a similar guarantee if a different way? As a tool to aid distro reviewers, modversions has some value, but the debug info parsing tools that have been mentioned in this thread seem superior (not that I've tested them). On the other hand the big advantage of modvers

Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-12 Thread Stanislav Kozina
A runtime check is still done, with per-module vermagic which distros can change when they bump the ABI version. Is it really necessary to have more than that (i.e., per-symbol versioning)? From my point of view, it is. We need to allow changing ABI for some modules while maintaining it for oth

Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-12 Thread Stanislav Kozina
Hello, That said, a dwarf based checker tool should be able to do as good a job (maybe a bit better because report is very informative and it may pick up compiler alignments or padding options). So, Nicholas was kind enough to send me the two Linux Kernel binaries that he built with the tiny li

Re: [PATCH] x86/kbuild: enable modversions for symbols exported from asm

2016-12-15 Thread Stanislav Kozina
Yeah it's great work, so is Stanislav's checker. I wouldn't mind having a kernel-centric checker tool merged in the kernel if it is small, maintained, and does a sufficient job for distros. I'd be very happy to see the resulting tool in the kernel tree, as it needs to be kept in sync with any