linux-kernel - [patch] FLAT binaries: drop BINFMT

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Message-Id: <200802111235.03761.vapier.adi@gmail.com>
Date:	Mon, 11 Feb 2008 12:35:03 -0500
From:	Mike Frysinger <vapier.adi@...il.com>
To:	gerg@...inux.org
Cc:	linux-kernel@...r.kernel.org, bernds_cb1@...nline.de
Subject: [patch] FLAT binaries: drop BINFMT_FLAT bad header magic warning

The warning issued by fs/binfmt_flat.c when the format handler is given a
non-FLAT and non-script executable is annoying to say the least when working
with FDPIC ELF objects.  If you build a kernel that supports both FLAT and
FDPIC ELFs on no-mmu, every time you execute an FDPIC ELF, the kernel spits
out this message.  While I understand a lot of newcomers to the no-mmu world
screw up generation of FLAT binaries, this warning is not usable for systems
that support more than just FLAT.

Signed-off-by: Jie Zhang <jie.zhang@...log.com>
Signed-off-by: Mike Frysinger <vapier@...too.org>
CC: Bernd Schmidt <bernds_cb1@...nline.de>
CC: Greg Ungerer <gerg@...pgear.com>
---
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index d8a02f1..0498b18 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -443,12 +443,12 @@ static int load_flat_file(struct linux_binprm * bprm,
 
 	if (strncmp(hdr->magic, "bFLT", 4)) {
 		/*
+		 * Previously, here was a printk to tell people
+		 *   "BINFMT_FLAT: bad header magic".
+		 * But for the kernel which also use ELF FD-PIC format, this
+		 * error message is confusing.
 		 * because a lot of people do not manage to produce good
-		 * flat binaries,  we leave this printk to help them realise
-		 * the problem.  We only print the error if its not a script file
 		 */
-		if (strncmp(hdr->magic, "#!", 2))
-			printk("BINFMT_FLAT: bad header magic\n");
 		ret = -ENOEXEC;
 		goto err;
 	}
--
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