linux-kernel - [PATCH 2/5] x86/pkeys: rename write

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Message-Id: <20210527235113.C5DAFE12@viggo.jf.intel.com>
Date:   Thu, 27 May 2021 16:51:13 -0700
From:   Dave Hansen <dave.hansen@...ux.intel.com>
To:     linux-mm@...ck.org
Cc:     linux-kernel@...r.kernel.org,
        Dave Hansen <dave.hansen@...ux.intel.com>, tglx@...utronix.de,
        mingo@...hat.com, bp@...en8.de, x86@...nel.org, luto@...nel.org,
        shuah@...nel.org, babu.moger@....com, dave.kleikamp@...cle.com,
        linuxram@...ibm.com, bauerman@...ux.ibm.com, bigeasy@...utronix.de
Subject: [PATCH 2/5] x86/pkeys: rename write_pkru()


From: Dave Hansen <dave.hansen@...ux.intel.com>

write_pkru() was once concerned purely with writing to the PKRU register.
However, the current task XSAVE buffer must also be updated in a
coordinated way.

Change the naming to reflect that this is an operation which applies to
a task (current) and its state in addition to the register itself.

Signed-off-by: Dave Hansen <dave.hansen@...ux.intel.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Ingo Molnar <mingo@...hat.com>
Cc: Borislav Petkov <bp@...en8.de>
Cc: x86@...nel.org
Cc: Andy Lutomirski <luto@...nel.org>
Cc: Shuah Khan <shuah@...nel.org>
Cc: Babu Moger <babu.moger@....com>
Cc: Dave Kleikamp <dave.kleikamp@...cle.com>
Cc: Ram Pai <linuxram@...ibm.com>
Cc: Thiago Jung Bauermann <bauerman@...ux.ibm.com>
Cc: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
---

 b/arch/x86/include/asm/fpu/xstate.h |    6 +++++-
 b/arch/x86/kernel/fpu/xstate.c      |    2 +-
 b/arch/x86/mm/pkeys.c               |    2 +-
 3 files changed, 7 insertions(+), 3 deletions(-)

diff -puN arch/x86/include/asm/fpu/xstate.h~rename-write_pkru arch/x86/include/asm/fpu/xstate.h
--- a/arch/x86/include/asm/fpu/xstate.h~rename-write_pkru	2021-05-27 16:40:24.618705468 -0700
+++ b/arch/x86/include/asm/fpu/xstate.h	2021-05-27 16:40:24.631705468 -0700
@@ -124,7 +124,11 @@ static inline u32 read_pkru(void)
 	return 0;
 }
 
-static inline void write_pkru(u32 pkru)
+/*
+ * Update all of the PKRU state for the current task:
+ * PKRU register and PKRU xstate.
+ */
+static inline void current_write_pkru(u32 pkru)
 {
 	struct pkru_state *pk;
 
diff -puN arch/x86/kernel/fpu/xstate.c~rename-write_pkru arch/x86/kernel/fpu/xstate.c
--- a/arch/x86/kernel/fpu/xstate.c~rename-write_pkru	2021-05-27 16:40:24.620705468 -0700
+++ b/arch/x86/kernel/fpu/xstate.c	2021-05-27 16:40:24.633705468 -0700
@@ -1026,7 +1026,7 @@ int arch_set_user_pkey_access(struct tas
 	old_pkru &= ~((PKRU_AD_BIT|PKRU_WD_BIT) << pkey_shift);
 
 	/* Write old part along with new part: */
-	write_pkru(old_pkru | new_pkru_bits);
+	current_write_pkru(old_pkru | new_pkru_bits);
 
 	return 0;
 }
diff -puN arch/x86/mm/pkeys.c~rename-write_pkru arch/x86/mm/pkeys.c
--- a/arch/x86/mm/pkeys.c~rename-write_pkru	2021-05-27 16:40:24.626705468 -0700
+++ b/arch/x86/mm/pkeys.c	2021-05-27 16:40:24.634705468 -0700
@@ -139,7 +139,7 @@ void copy_init_pkru_to_fpregs(void)
 	 * Override the PKRU state that came from 'init_fpstate'
 	 * with the baseline from the process.
 	 */
-	write_pkru(init_pkru_value_snapshot);
+	current_write_pkru(init_pkru_value_snapshot);
 }
 
 static ssize_t init_pkru_read_file(struct file *file, char __user *user_buf,
_