PCI/ASPM: Handle PCI-to-PCIe bridges as roots of PCIe hierarchies

In a struct pcie_link_state, link->root points to the pcie_link_state of
the root of the PCIe hierarchy.  For the topmost link, this points to
itself (link->root = link).  For others, we copy the pointer from the
parent (link->root = link->parent->root).

Previously we recognized that Root Ports originated PCIe hierarchies, but
we treated PCI/PCI-X to PCIe Bridges as being in the middle of the
hierarchy, and when we tried to copy the pointer from link->parent->root,
there was no parent, and we dereferenced a NULL pointer:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
  IP: [<ffffffff9e424350>] pcie_aspm_init_link_state+0x170/0x820

Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just
like Root Ports do, so link->root for these devices should also point to
itself.

Fixes: 51ebfc92b72b ("PCI: Enumerate switches below PCI-to-PCIe bridges")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181
Tested-by: lists@ssl-mail.com
Tested-by: Jayachandran C. <jnair@caviumnetworks.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v4.2+

path: root/include/crypto/serpent.h

/*
 * Common values for serpent algorithms
 */

#ifndef _CRYPTO_SERPENT_H
#define _CRYPTO_SERPENT_H

#include <linux/types.h>
#include <linux/crypto.h>

#define SERPENT_MIN_KEY_SIZE		  0
#define SERPENT_MAX_KEY_SIZE		 32
#define SERPENT_EXPKEY_WORDS		132
#define SERPENT_BLOCK_SIZE		 16

struct serpent_ctx {
	u32 expkey[SERPENT_EXPKEY_WORDS];
};

int __serpent_setkey(struct serpent_ctx *ctx, const u8 *key,
		     unsigned int keylen);
int serpent_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen);

void __serpent_encrypt(struct serpent_ctx *ctx, u8 *dst, const u8 *src);
void __serpent_decrypt(struct serpent_ctx *ctx, u8 *dst, const u8 *src);

#endif