Messages in this thread |  | | Date | Tue, 8 Apr 2025 18:58:49 -0700 | | From | Josh Poimboeuf <> | | Subject | Re: [PATCH] scripts/mksysmap: skip objtool __pfx_ symbols |
| |
On Fri, Mar 28, 2025 at 11:48:19AM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@arndb.de> > > The recently added testcase for overly long symbols triggers when > CONFIG_FUNCTION_PADDING_CFI is set: > > Symbol __pfx_snnnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnnnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nnng1h2i3j4k5l6m7ng1h2i3j4k5l6m7nng1h2i3j4k5l6m7ng1h2i3j4k5l6m7n too long for kallsyms (517 >= 512). > Please increase KSYM_NAME_LEN both in kernel and kallsyms.c > > Change the mksymtab table so the prefixed symbols are not included > in kallsyms. > > Fixes: c104c16073b7 ("Kunit to check the longest symbol length") > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
I'm not sure we want to remove the __pfx_ symbols from kallsyms. There can be actual code there.
For example, FineIBT writes code in the __pfx area which can trigger an #UD. And we'd want a sane backtrace for that.
Maybe objtool should error out when trying to prefix a function with a name longer than (KSYM_NAME_LEN - 6). And the kunit test could be adjusted accordingly for CONFIG_PREFIX_SYMBOLS.
-- Josh
|  |