Hello, On Mon, Mar 13, 2023 at 09:32:16PM +0100, Andrea Righi wrote: > On Wed, Jan 11, 2023 at 04:11:51PM +0000, Gary Guo wrote: > > Currently modversion uses a fixed size array of size (64 - sizeof(long)) > > to store symbol names, thus placing a hard limit on length of symbols. > > Rust symbols (which encodes crate and module names) can be quite a bit > > longer. The length limit in kallsyms is increased to 512 for this reason. > > > > It's a waste of space to simply expand the fixed array size to 512 in > > modversion info entries. I therefore make it variably sized, with offset > > to the next entry indicated by the initial "next" field. > > > > In addition to supporting longer-than-56/60 byte symbols, this patch also > > reduce the size for short symbols by getting rid of excessive 0 paddings. > > There are still some zero paddings to ensure "next" and "crc" fields are > > properly aligned. > > > > This patch does have a tiny drawback that it makes ".mod.c" files generated > > a bit less easy to read, as code like > > > > "\x08\x00\x00\x00\x78\x56\x34\x12" > > "symbol\0\0" > > > > is generated as opposed to > > > > { 0x12345678, "symbol" }, > > > > because the structure is now variable-length. But hopefully nobody reads > > the generated file :) > > > > Link: b8a94bfb3395 ("kallsyms: increase maximum kernel symbol length to > > 512") > > Link: https://github.com/Rust-for-Linux/linux/pull/379 > > > > Signed-off-by: Gary Guo <g...@garyguo.net> > > Is there any newer version of this patch? > > I'm doing some tests with it, but I'm getting boot failures on ppc64 > with this applied (at boot kernel is spitting out lots of oops'es and > unfortunately it's really hard to copy paste or just read them from the > console).
Are you using the ELF ABI v1 or v2? v1 may have some additional issues when it comes to these symbol tables. Thanks Michal