| Message ID | 20230317113538.10878-16-andy.chiu@sifive.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | riscv: Add vector ISA support | expand |
On Fri, Mar 17, 2023 at 11:35:34AM +0000, Andy Chiu wrote: > Some extensions, such as Vector, dynamically change footprint on a > signal frame, so MINSIGSTKSZ is no longer accurate. For example, an > RV64V implementation with vlen = 512 may occupy 2K + 40 + 12 Bytes of a > signal frame with the upcoming support. And processes that do not > execute any vector instructions do not need to reserve the extra > sigframe. So we need a way to guard the allocation size of the sigframe > at process runtime according to current status of V. > > Thus, provide the function sigaltstack_size_valid() to validate its size > based on current allocation status of supported extensions. > > Signed-off-by: Andy Chiu <andy.chiu@sifive.com> > --- > arch/riscv/kernel/signal.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c > index d2d9232498ca..b8ad9a7fc0ad 100644 > --- a/arch/riscv/kernel/signal.c > +++ b/arch/riscv/kernel/signal.c > @@ -494,3 +494,11 @@ void __init init_rt_signal_env(void) > */ > signal_minsigstksz = get_rt_frame_size(true); > } > + > +#ifdef CONFIG_DYNAMIC_SIGFRAME > +bool sigaltstack_size_valid(size_t ss_size) > +{ > + return ss_size > get_rt_frame_size(false); btw, thanks for using a clearer function name w/ the s/cal/get/ change & for the expansion on the commit message. Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Thanks, Conor. > +} > +#endif /* CONFIG_DYNAMIC_SIGFRAME */ > + > -- > 2.17.1 > >
diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c index d2d9232498ca..b8ad9a7fc0ad 100644 --- a/arch/riscv/kernel/signal.c +++ b/arch/riscv/kernel/signal.c @@ -494,3 +494,11 @@ void __init init_rt_signal_env(void) */ signal_minsigstksz = get_rt_frame_size(true); } + +#ifdef CONFIG_DYNAMIC_SIGFRAME +bool sigaltstack_size_valid(size_t ss_size) +{ + return ss_size > get_rt_frame_size(false); +} +#endif /* CONFIG_DYNAMIC_SIGFRAME */ +
Some extensions, such as Vector, dynamically change footprint on a signal frame, so MINSIGSTKSZ is no longer accurate. For example, an RV64V implementation with vlen = 512 may occupy 2K + 40 + 12 Bytes of a signal frame with the upcoming support. And processes that do not execute any vector instructions do not need to reserve the extra sigframe. So we need a way to guard the allocation size of the sigframe at process runtime according to current status of V. Thus, provide the function sigaltstack_size_valid() to validate its size based on current allocation status of supported extensions. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> --- arch/riscv/kernel/signal.c | 8 ++++++++ 1 file changed, 8 insertions(+)