Revision 2205cbe8ecaf5f3ab911cef839c94d05ea5b0c76 authored by Alex Chiang on 19 January 2010, 23:55:41 UTC, committed by Len Brown on 20 January 2010, 04:43:47 UTC
Commit 78f1699 (ACPI: processor: call _PDC early) blindly walks
the namespace and calls _PDC on every processor object it finds.

This change may cause issues on platforms that declare dummy
values for SSDTs on non-present processors (disabled in MADT).
When we call _PDC and dynamically attempt to execute the AML
Load() op on these dummy SSDTs, there's no telling what might
happen.

Rather than finding every platform that has bogus SSDTs, restrict
early _PDC calls to platforms that are known to need early
evaluation of _PDC.

This is a minimal, temporary fix (given the context of the
current release cycle). A real solution of checking the MADT for
non-present processors will be written for the next merge window.

References:

	http://bugzilla.kernel.org/show_bug.cgi?id=14710
	http://bugzilla.kernel.org/show_bug.cgi?id=14954

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
1 parent 24bc734
Raw File
lzo.c
/*
 * Cryptographic API.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/crypto.h>
#include <linux/vmalloc.h>
#include <linux/lzo.h>

struct lzo_ctx {
	void *lzo_comp_mem;
};

static int lzo_init(struct crypto_tfm *tfm)
{
	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);

	ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS);
	if (!ctx->lzo_comp_mem)
		return -ENOMEM;

	return 0;
}

static void lzo_exit(struct crypto_tfm *tfm)
{
	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);

	vfree(ctx->lzo_comp_mem);
}

static int lzo_compress(struct crypto_tfm *tfm, const u8 *src,
			    unsigned int slen, u8 *dst, unsigned int *dlen)
{
	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
	int err;

	err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx->lzo_comp_mem);

	if (err != LZO_E_OK)
		return -EINVAL;

	*dlen = tmp_len;
	return 0;
}

static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src,
			      unsigned int slen, u8 *dst, unsigned int *dlen)
{
	int err;
	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */

	err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);

	if (err != LZO_E_OK)
		return -EINVAL;

	*dlen = tmp_len;
	return 0;

}

static struct crypto_alg alg = {
	.cra_name		= "lzo",
	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
	.cra_ctxsize		= sizeof(struct lzo_ctx),
	.cra_module		= THIS_MODULE,
	.cra_list		= LIST_HEAD_INIT(alg.cra_list),
	.cra_init		= lzo_init,
	.cra_exit		= lzo_exit,
	.cra_u			= { .compress = {
	.coa_compress 		= lzo_compress,
	.coa_decompress  	= lzo_decompress } }
};

static int __init lzo_mod_init(void)
{
	return crypto_register_alg(&alg);
}

static void __exit lzo_mod_fini(void)
{
	crypto_unregister_alg(&alg);
}

module_init(lzo_mod_init);
module_exit(lzo_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO Compression Algorithm");
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