All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Michael Ellerman <mpe@ellerman.id.au>,
	ldv@altlinux.org, viro@zeniv.linux.org.uk
Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [RFC PATCH v1 03/19] powerpc/ptrace: Consolidate reg index calculation
Date: Wed, 12 Aug 2020 12:05:54 +0000 (UTC)	[thread overview]
Message-ID: <17430b14a0b2a9da8fc24dfaeca79aec0180df5c.1597233555.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>

Today we have:

	#ifdef CONFIG_PPC32
		index = addr >> 2;
		if ((addr & 3) || child->thread.regs == NULL)
	#else
		index = addr >> 3;
		if ((addr & 7))
	#endif

sizeof(long) has value 4 for PPC32 and value 8 for PPC64.

Dividing by 4 is equivalent to >> 2 and dividing by 8 is equivalent
to >> 3.

And 3 and 7 are respectively (sizeof(long) - 1).

Use sizeof(long) to get rid of the #ifdef CONFIG_PPC32 and consolidate
the calculation and checking.

thread.regs have to be not NULL on both PPC32 and PPC64 so adding
that test on PPC64 is harmless.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/ptrace/ptrace.c | 20 ++++----------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index f6e51be47c6e..0b4645a7a1b4 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -55,14 +55,8 @@ long arch_ptrace(struct task_struct *child, long request,
 
 		ret = -EIO;
 		/* convert to index and check */
-#ifdef CONFIG_PPC32
-		index = addr >> 2;
-		if ((addr & 3) || (index > PT_FPSCR)
-		    || (child->thread.regs == NULL))
-#else
-		index = addr >> 3;
-		if ((addr & 7) || (index > PT_FPSCR))
-#endif
+		index = addr / sizeof(long);
+		if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
 			break;
 
 		CHECK_FULL_REGS(child->thread.regs);
@@ -90,14 +84,8 @@ long arch_ptrace(struct task_struct *child, long request,
 
 		ret = -EIO;
 		/* convert to index and check */
-#ifdef CONFIG_PPC32
-		index = addr >> 2;
-		if ((addr & 3) || (index > PT_FPSCR)
-		    || (child->thread.regs == NULL))
-#else
-		index = addr >> 3;
-		if ((addr & 7) || (index > PT_FPSCR))
-#endif
+		index = addr / sizeof(long);
+		if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
 			break;
 
 		CHECK_FULL_REGS(child->thread.regs);
-- 
2.25.0


WARNING: multiple messages have this Message-ID (diff)
From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Michael Ellerman <mpe@ellerman.id.au>,
	 ldv@altlinux.org, viro@zeniv.linux.org.uk
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: [RFC PATCH v1 03/19] powerpc/ptrace: Consolidate reg index calculation
Date: Wed, 12 Aug 2020 12:05:54 +0000 (UTC)	[thread overview]
Message-ID: <17430b14a0b2a9da8fc24dfaeca79aec0180df5c.1597233555.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <cover.1597233555.git.christophe.leroy@csgroup.eu>

Today we have:

	#ifdef CONFIG_PPC32
		index = addr >> 2;
		if ((addr & 3) || child->thread.regs == NULL)
	#else
		index = addr >> 3;
		if ((addr & 7))
	#endif

sizeof(long) has value 4 for PPC32 and value 8 for PPC64.

Dividing by 4 is equivalent to >> 2 and dividing by 8 is equivalent
to >> 3.

And 3 and 7 are respectively (sizeof(long) - 1).

Use sizeof(long) to get rid of the #ifdef CONFIG_PPC32 and consolidate
the calculation and checking.

thread.regs have to be not NULL on both PPC32 and PPC64 so adding
that test on PPC64 is harmless.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/ptrace/ptrace.c | 20 ++++----------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index f6e51be47c6e..0b4645a7a1b4 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -55,14 +55,8 @@ long arch_ptrace(struct task_struct *child, long request,
 
 		ret = -EIO;
 		/* convert to index and check */
-#ifdef CONFIG_PPC32
-		index = addr >> 2;
-		if ((addr & 3) || (index > PT_FPSCR)
-		    || (child->thread.regs == NULL))
-#else
-		index = addr >> 3;
-		if ((addr & 7) || (index > PT_FPSCR))
-#endif
+		index = addr / sizeof(long);
+		if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
 			break;
 
 		CHECK_FULL_REGS(child->thread.regs);
@@ -90,14 +84,8 @@ long arch_ptrace(struct task_struct *child, long request,
 
 		ret = -EIO;
 		/* convert to index and check */
-#ifdef CONFIG_PPC32
-		index = addr >> 2;
-		if ((addr & 3) || (index > PT_FPSCR)
-		    || (child->thread.regs == NULL))
-#else
-		index = addr >> 3;
-		if ((addr & 7) || (index > PT_FPSCR))
-#endif
+		index = addr / sizeof(long);
+		if ((addr & (sizeof(long) - 1)) || (index > PT_FPSCR) || !child->thread.regs)
 			break;
 
 		CHECK_FULL_REGS(child->thread.regs);
-- 
2.25.0


  parent reply	other threads:[~2020-08-12 12:07 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-12 12:05 [RFC PATCH v1 00/19] powerpc: Switch signal 32 to using user_access_begin() and friends Christophe Leroy
2020-08-12 12:05 ` Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 01/19] powerpc/signal: Move inline functions in signal.h Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 02/19] powerpc/ptrace: Move declaration of ptrace_get_reg() and ptrace_set_reg() Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 15:47   ` kernel test robot
2020-08-12 12:05 ` Christophe Leroy [this message]
2020-08-12 12:05   ` [RFC PATCH v1 03/19] powerpc/ptrace: Consolidate reg index calculation Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 04/19] powerpc/ptrace: Create ptrace_get_fpr() and ptrace_put_fpr() Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 05/19] powerpc/signal: Don't manage floating point regs when no FPU Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 06/19] powerpc/32s: Allow deselecting CONFIG_PPC_FPU on mpc832x Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 07/19] powerpc/signal: Move access_ok() out of get_sigframe() Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 12:05 ` [RFC PATCH v1 08/19] powerpc/signal: Remove get_clean_sp() Christophe Leroy
2020-08-12 12:05   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 09/19] powerpc/signal: Call get_tm_stackpointer() from get_sigframe() Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 10/19] powerpc/signal: Refactor bad frame logging Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 11/19] powerpc/signal32: Simplify logging in handle_rt_signal32() Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 12/19] powerpc/signal32: Regroup copies in save_user_regs() and save_tm_user_regs() Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 13/19] powerpc/signal32: Create 'unsafe' versions of copy_[ck][fpr/vsx]_to_user() Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 14/19] powerpc/signal32: Switch save_user_regs() and save_tm_user_regs() to user_access_begin() logic Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 15/19] powerpc/signal32: Switch handle_signal32() " Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 16/19] powerpc/signal32: Switch handle_rt_signal32() " Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 17/19] signal: Add unsafe_put_compat_sigset() Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 12:06 ` [RFC PATCH v1 18/19] powerpc/signal32: Add and use unsafe_put_sigset_t() Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy
2020-08-12 14:01   ` kernel test robot
2020-08-12 12:06 ` [RFC PATCH v1 19/19] powerpc/signal32: Switch swap_context() to user_access_begin() logic Christophe Leroy
2020-08-12 12:06   ` Christophe Leroy

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=17430b14a0b2a9da8fc24dfaeca79aec0180df5c.1597233555.git.christophe.leroy@csgroup.eu \
    --to=christophe.leroy@csgroup.eu \
    --cc=benh@kernel.crashing.org \
    --cc=ldv@altlinux.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    --cc=paulus@samba.org \
    --cc=viro@zeniv.linux.org.uk \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.