![H. Peter Anvin](/assets/img/avatar_default.png)
Fix incorrect assembly constraints. In particular, fix memory constraints used inside push..pop, which can cause invalid operation since gcc may generate %esp-relative references. Additionally: outl() should have "dN" not "dn". query_mca() shouldn't listen 16/32-bit registers in an 8-bit only context. has_eflag(): the "mask" is only used well after both the stack pointer and the output registers have been touched; this requires the output registers to be earlyclobbers (=&) and the input to exclude memory (so "ri", not "g"). Thanks to Etienne Lorrain and Chuck Ebbert for prompting this review. Cc: Etienne Lorrain <etienne_lorrain@yahoo.fr> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
47 lines
1 KiB
C
47 lines
1 KiB
C
/* -*- linux-c -*- ------------------------------------------------------- *
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright 2007 rPath, Inc. - All Rights Reserved
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*
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* This file is part of the Linux kernel, and is made available under
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* the terms of the GNU General Public License version 2.
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*
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* ----------------------------------------------------------------------- */
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/*
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* arch/i386/boot/voyager.c
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*
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* Get the Voyager config information
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*/
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#include "boot.h"
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#ifdef CONFIG_X86_VOYAGER
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int query_voyager(void)
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{
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u8 err;
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u16 es, di;
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/* Abuse the apm_bios_info area for this */
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u8 *data_ptr = (u8 *)&boot_params.apm_bios_info;
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data_ptr[0] = 0xff; /* Flag on config not found(?) */
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asm("pushw %%es ; "
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"int $0x15 ; "
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"setc %0 ; "
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"movw %%es, %1 ; "
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"popw %%es"
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: "=q" (err), "=r" (es), "=D" (di)
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: "a" (0xffc0));
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if (err)
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return -1; /* Not Voyager */
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set_fs(es);
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copy_from_fs(data_ptr, di, 7); /* Table is 7 bytes apparently */
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return 0;
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}
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#endif /* CONFIG_X86_VOYAGER */
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