From: Rafael David Tinoco <rafael.tinoco@linaro.org>
To: Russell King <linux@armlinux.org.uk>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>,
Rafael David Tinoco <rafael.tinoco@linaro.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Masahiro Yamada <yamada.masahiro@socionext.com>,
Thomas Gleixner <tglx@linutronix.de>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Vincent Whitchurch <vincent.whitchurch@axis.com>,
Timothy E Baldwin <T.E.Baldwin99@members.leeds.ac.uk>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: [PATCH] arm: always update thread_info->syscall
Date: Mon, 26 Nov 2018 20:53:35 -0200 [thread overview]
Message-ID: <20181126225335.10477-1-rafael.tinoco@linaro.org> (raw)
Right now, only way for task->thread_info->syscall to be updated is if
if _TIF_SYSCALL_WORK is set in current's task thread_info->flags
(similar to what has_syscall_work() checks for arm64).
This means that "->syscall" will only be updated if we are tracing the
syscalls through ptrace, for example. This is NOT the same behavior as
arm64, when pt_regs->syscallno is updated in the beginning of svc0
handler for *every* syscall entry.
This patch fixes the issue since this behavior is needed for
/proc/<pid>/syscall 1st argument to be correctly updated.
Link: https://bugs.linaro.org/show_bug.cgi?id=3783
Cc: <stable@vger.kernel.org> # v4.4 v4.9 v4.14 v4.19
Signed-off-by: Rafael David Tinoco <rafael.tinoco@linaro.org>
---
arch/arm/kernel/asm-offsets.c | 1 +
arch/arm/kernel/entry-common.S | 2 ++
2 files changed, 3 insertions(+)
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 3968d6c22455..bfe68a98e1c6 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -64,6 +64,7 @@ int main(void)
DEFINE(TI_USED_CP, offsetof(struct thread_info, used_cp));
DEFINE(TI_TP_VALUE, offsetof(struct thread_info, tp_value));
DEFINE(TI_FPSTATE, offsetof(struct thread_info, fpstate));
+ DEFINE(TI_SYSCALL, offsetof(struct thread_info, syscall));
#ifdef CONFIG_VFP
DEFINE(TI_VFPSTATE, offsetof(struct thread_info, vfpstate));
#ifdef CONFIG_SMP
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 0465d65d23de..557e2add4e83 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -257,6 +257,8 @@ local_restart:
tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls?
bne __sys_trace
+ str r7, [tsk, #TI_SYSCALL] @ update thread_info->syscall
+
invoke_syscall tbl, scno, r10, __ret_fast_syscall
add r1, sp, #S_OFF
--
2.20.0.rc1
next reply other threads:[~2018-11-26 22:53 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-26 22:53 Rafael David Tinoco [this message]
2018-11-26 23:33 ` [PATCH] arm: always update thread_info->syscall Russell King - ARM Linux
2018-11-26 23:41 ` Russell King - ARM Linux
2018-11-26 23:44 ` Russell King - ARM Linux
2018-11-27 10:30 ` Rafael David Tinoco
2018-11-27 10:56 ` Russell King - ARM Linux
2018-11-27 15:35 ` Russell King - ARM Linux
2018-11-27 15:48 ` David Laight
2018-11-27 20:52 ` Rafael David Tinoco
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=20181126225335.10477-1-rafael.tinoco@linaro.org \
--to=rafael.tinoco@linaro.org \
--cc=T.E.Baldwin99@members.leeds.ac.uk \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=mathieu.desnoyers@efficios.com \
--cc=ndesaulniers@google.com \
--cc=stable@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=vincent.whitchurch@axis.com \
--cc=vladimir.murzin@arm.com \
--cc=yamada.masahiro@socionext.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).