diff mbox series

[-next,v21,16/27] riscv: signal: validate altstack to reflect Vector

Message ID 20230605110724.21391-17-andy.chiu@sifive.com (mailing list archive)
State Accepted
Commit 76e22fdc2c2658ab595cdda7368d43d2dc16f3f4
Headers show
Series riscv: Add vector ISA support | expand

Checks

Context Check Description
conchuod/cover_letter success Series has a cover letter
conchuod/tree_selection success Guessed tree name to be for-next at HEAD 90502d51ab90
conchuod/fixes_present success Fixes tag not required for -next series
conchuod/maintainers_pattern success MAINTAINERS pattern errors before the patch: 6 and now 6
conchuod/verify_signedoff success Signed-off-by tag matches author and committer
conchuod/kdoc success Errors and warnings before: 0 this patch: 0
conchuod/build_rv64_clang_allmodconfig success Errors and warnings before: 8 this patch: 8
conchuod/module_param success Was 0 now: 0
conchuod/build_rv64_gcc_allmodconfig success Errors and warnings before: 8 this patch: 8
conchuod/build_rv32_defconfig success Build OK
conchuod/dtb_warn_rv64 success Errors and warnings before: 3 this patch: 3
conchuod/header_inline success No static functions without inline keyword in header files
conchuod/checkpatch success total: 0 errors, 0 warnings, 0 checks, 10 lines checked
conchuod/build_rv64_nommu_k210_defconfig success Build OK
conchuod/verify_fixes success No Fixes tag
conchuod/build_rv64_nommu_virt_defconfig success Build OK

Commit Message

Andy Chiu June 5, 2023, 11:07 a.m. UTC 
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>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
---
 arch/riscv/kernel/signal.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff mbox series

Patch

diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
index f117641c1c49..180d951d3624 100644
--- a/arch/riscv/kernel/signal.c
+++ b/arch/riscv/kernel/signal.c
@@ -476,3 +476,10 @@  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 */