Messages in this thread | | | Date | Tue, 31 Jan 2023 12:51:33 +0000 | From | Catalin Marinas <> | Subject | Re: [PATCH v2 0/6] arm64/signal: Signal handling cleanups |
| |
Hi Mark,
On Tue, Jan 03, 2023 at 08:25:15PM +0000, Mark Brown wrote: > This series collects a number of small cleanups to the signal handling > code which removes redundant validation of size information and avoids > reading the same data from userspace twice. > > There are some overlaps with both the TPIDR2 signal handling and SME2 > serieses which are also in flight, applying this will require > adjustments in those serieses and vice versa. [...] > Mark Brown (6): > arm64/signal: Don't redundantly verify FPSIMD magic > arm64/signal: Remove redundant size validation from parse_user_sigframe() > arm64/signal: Make interface for restore_fpsimd_context() consistent
I'm fine with the first three patches, they seem correct and make the frame checking more consistent.
> arm64/signal: Avoid rereading context frame sizes > arm64/signal: Only read new data when parsing the SVE context > arm64/signal: Only read new data when parsing the ZA context
I'm not sure these add much to the code readability (and the performance improvement I guess is negligible). We avoid some copy_from_user() into the context structures but rely on data read previously or some get_user() into local variables. Personally I'd make the restore_fpsimd_context() also do a copy_from_user() for consistency with the current sve and za frames restoring.
Personal preference, not sure whether Will has the same view.
-- Catalin
| |