linux-kernel - [tip: x86/paravirt] x86/paravirt: Make the struct paravirt_patch

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Date:   Mon, 13 Nov 2023 11:52:43 -0000
From:   "tip-bot2 for Hou Wenlong" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Nadav Amit <namit@...are.com>,
        Hou Wenlong <houwenlong.hwl@...group.com>,
        "Borislav Petkov (AMD)" <bp@...en8.de>,
        Juergen Gross <jgross@...e.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: [tip: x86/paravirt] x86/paravirt: Make the struct paravirt_patch_site packed

The following commit has been merged into the x86/paravirt branch of tip:

Commit-ID:     fe22bc430c9d24394e541e16e0941a075f02fcb7
Gitweb:        https://git.kernel.org/tip/fe22bc430c9d24394e541e16e0941a075f02fcb7
Author:        Hou Wenlong <houwenlong.hwl@...group.com>
AuthorDate:    Fri, 09 Jun 2023 17:45:32 +08:00
Committer:     Borislav Petkov (AMD) <bp@...en8.de>
CommitterDate: Mon, 13 Nov 2023 12:43:50 +01:00

x86/paravirt: Make the struct paravirt_patch_site packed

Similar to struct alt_instr, make the struct paravirt_patch_site packed
and get rid of all the .align directives and save 2 bytes for one
PARA_SITE entry on X86_64.

  [ bp: Massage commit message. ]

Suggested-by: Nadav Amit <namit@...are.com>
Signed-off-by: Hou Wenlong <houwenlong.hwl@...group.com>
Signed-off-by: Borislav Petkov (AMD) <bp@...en8.de>
Reviewed-by: Juergen Gross <jgross@...e.com>
Link: https://lore.kernel.org/r/6dcb20159ded36586c5f7f2ae159e4e030256627.1686301237.git.houwenlong.hwl@antgroup.com
---
 arch/x86/include/asm/paravirt.h       | 2 --
 arch/x86/include/asm/paravirt_types.h | 4 +---
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index d9384e9..693c61d 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -748,11 +748,9 @@ void native_pv_lock_init(void) __init;
 	ops;					\
 772:;						\
 	.pushsection .parainstructions,"a";	\
-	 .align	4;				\
 	 .long 771b-.;				\
 	 .byte ptype;				\
 	 .byte 772b-771b;			\
-	 .align 4;				\
 	.popsection
 
 
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index e1bfb71..f4fb2e3 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -8,7 +8,7 @@ struct paravirt_patch_site {
 	s32 instr_offset;	/* original instructions */
 	u8 type;		/* type of this instruction */
 	u8 len;			/* length of original instruction */
-};
+} __packed;
 #endif
 
 #ifdef CONFIG_PARAVIRT
@@ -263,11 +263,9 @@ extern struct paravirt_patch_template pv_ops;
 #define _paravirt_alt(insn_string, type)		\
 	"771:\n\t" insn_string "\n" "772:\n"		\
 	".pushsection .parainstructions,\"a\"\n"	\
-	"  .align 4\n"					\
 	"  .long 771b-.\n"				\
 	"  .byte " type "\n"				\
 	"  .byte 772b-771b\n"				\
-	"  .align 4\n"					\
 	".popsection\n"
 
 /* Generate patchable code, with the default asm parameters. */