linux-riscv.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Sergey Matyukevich <geomatsi@gmail.com>
To: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-kselftest@vger.kernel.org
Cc: Paul Walmsley <pjw@kernel.org>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Alexandre Ghiti <alex@ghiti.fr>, Oleg Nesterov <oleg@redhat.com>,
	Shuah Khan <shuah@kernel.org>, Thomas Huth <thuth@redhat.com>,
	Charlie Jenkins <charlie@rivosinc.com>,
	Andy Chiu <andybnac@gmail.com>,
	Samuel Holland <samuel.holland@sifive.com>,
	Joel Granados <joel.granados@kernel.org>,
	Conor Dooley <conor.dooley@microchip.com>,
	Yong-Xuan Wang <yongxuan.wang@sifive.com>,
	Heiko Stuebner <heiko@sntech.de>,
	Sergey Matyukevich <geomatsi@gmail.com>,
	Ilya Mamay <mmamayka01@gmail.com>
Subject: [PATCH v4 2/9] riscv: ptrace: return ENODATA for inactive vector extension
Date: Sat,  8 Nov 2025 22:41:41 +0300	[thread overview]
Message-ID: <20251108194207.1257866-3-geomatsi@gmail.com> (raw)
In-Reply-To: <20251108194207.1257866-1-geomatsi@gmail.com>

From: Ilya Mamay <mmamayka01@gmail.com>

Currently, ptrace returns EINVAL when the vector extension is supported
but not yet activated for the traced process. This error code is not
always appropriate since the ptrace arguments may be valid.

Debug tools like gdbserver expect ENODATA when the requested register
set is not active, e.g. see [1]. This expectation seems to be more
appropriate, so modify the vector ptrace implementation to return:
- EINVAL when V extension is not supported
- ENODATA when V extension is supported but not active

[1] https://github.com/bminor/binutils-gdb/blob/637f25e88675fa47e47f9cc5e2cf37384836b8a2/gdbserver/linux-low.cc#L5020

Signed-off-by: Ilya Mamay <mmamayka01@gmail.com>
---
 arch/riscv/kernel/ptrace.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
index 8e86305831ea..906cf1197edc 100644
--- a/arch/riscv/kernel/ptrace.c
+++ b/arch/riscv/kernel/ptrace.c
@@ -95,9 +95,12 @@ static int riscv_vr_get(struct task_struct *target,
 	struct __riscv_v_ext_state *vstate = &target->thread.vstate;
 	struct __riscv_v_regset_state ptrace_vstate;
 
-	if (!riscv_v_vstate_query(task_pt_regs(target)))
+	if (!has_vector())
 		return -EINVAL;
 
+	if (!riscv_v_vstate_query(task_pt_regs(target)))
+		return -ENODATA;
+
 	/*
 	 * Ensure the vector registers have been saved to the memory before
 	 * copying them to membuf.
@@ -130,9 +133,12 @@ static int riscv_vr_set(struct task_struct *target,
 	struct __riscv_v_ext_state *vstate = &target->thread.vstate;
 	struct __riscv_v_regset_state ptrace_vstate;
 
-	if (!riscv_v_vstate_query(task_pt_regs(target)))
+	if (!has_vector())
 		return -EINVAL;
 
+	if (!riscv_v_vstate_query(task_pt_regs(target)))
+		return -ENODATA;
+
 	/* Copy rest of the vstate except datap */
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ptrace_vstate, 0,
 				 sizeof(struct __riscv_v_regset_state));
-- 
2.51.0


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

  parent reply	other threads:[~2025-11-08 19:42 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-08 19:41 [PATCH v4 0/9] riscv: vector: misc ptrace fixes for debug use-cases Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 1/9] selftests: riscv: test ptrace vector interface Sergey Matyukevich
2025-11-08 19:41 ` Sergey Matyukevich [this message]
2025-11-08 19:41 ` [PATCH v4 3/9] selftests: riscv: verify initial vector state with ptrace Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 4/9] riscv: vector: init vector context with proper vlenb Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 5/9] riscv: csr: define vtype registers elements Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 6/9] riscv: ptrace: validate input vector csr registers Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 7/9] selftests: riscv: verify ptrace rejects invalid vector csr inputs Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 8/9] selftests: riscv: verify ptrace accepts valid vector csr values Sergey Matyukevich
2025-11-08 19:41 ` [PATCH v4 9/9] selftests: riscv: verify syscalls discard vector context Sergey Matyukevich

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20251108194207.1257866-3-geomatsi@gmail.com \
    --to=geomatsi@gmail.com \
    --cc=alex@ghiti.fr \
    --cc=andybnac@gmail.com \
    --cc=charlie@rivosinc.com \
    --cc=conor.dooley@microchip.com \
    --cc=heiko@sntech.de \
    --cc=joel.granados@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=mmamayka01@gmail.com \
    --cc=oleg@redhat.com \
    --cc=palmer@dabbelt.com \
    --cc=pjw@kernel.org \
    --cc=samuel.holland@sifive.com \
    --cc=shuah@kernel.org \
    --cc=thuth@redhat.com \
    --cc=yongxuan.wang@sifive.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).