Am Montag, 27. März 2023, 18:49:34 CEST schrieb Andy Chiu: > From: Vincent Chen <vincent.chen@xxxxxxxxxx> > > The vector register belongs to the signal context. They need to be stored > and restored as entering and leaving the signal handler. According to the > V-extension specification, the maximum length of the vector registers can > be 2^16. Hence, if userspace refers to the MINSIGSTKSZ to create a > sigframe, it may not be enough. To resolve this problem, this patch refers > to the commit 94b07c1f8c39c > ("arm64: signal: Report signal frame size to userspace via auxv") to enable > userspace to know the minimum required sigframe size through the auxiliary > vector and use it to allocate enough memory for signal context. > > Note that auxv always reports size of the sigframe as if V exists for > all starting processes, whenever the kernel has CONFIG_RISCV_ISA_V. The > reason is that users usually reference this value to allocate an > alternative signal stack, and the user may use V anytime. So the user > must reserve a space for V-context in sigframe in case that the signal > handler invokes after the kernel allocating V. > > Signed-off-by: Greentime Hu <greentime.hu@xxxxxxxxxx> > Signed-off-by: Vincent Chen <vincent.chen@xxxxxxxxxx> > Signed-off-by: Andy Chiu <andy.chiu@xxxxxxxxxx> > Acked-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> > Reviewed-by: Björn Töpel <bjorn@xxxxxxxxxxxx> > Reviewed-by: Guo Ren <guoren@xxxxxxxxxx> Reviewed-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx> Tested-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx>