/* * IBM RTAS driver interface to hvc_console.c * * (C) Copyright IBM Corporation 2001-2005 * (C) Copyright Red Hat, Inc. 2005 * * Author(s): Maximino Augilar * : Ryan S. Arnold * : Utz Bacher * : David Woodhouse * * inspired by drivers/char/hvc_console.c * written by Anton Blanchard and Paul Mackerras * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include "hvc_console.h" #define hvc_rtas_cookie 0x67781e15 struct hvc_struct *hvc_rtas_dev; static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE; static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE; static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf, int count) { int i; for (i = 0; i < count; i++) { if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i])) break; } return i; } static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count) { int i, c; for (i = 0; i < count; i++) { if (rtas_call(rtascons_get_char_token, 0, 2, &c)) break; buf[i] = c; } return i; } static const struct hv_ops hvc_rtas_get_put_ops = { .get_chars = hvc_rtas_read_console, .put_chars = hvc_rtas_write_console, }; static int __init hvc_rtas_init(void) { struct hvc_struct *hp; if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE) rtascons_put_char_token = rtas_token("put-term-char"); if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE) rtascons_get_char_token = rtas_token("get-term-char"); if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; BUG_ON(hvc_rtas_dev); /* Allocate an hvc_struct for the console device we instantiated * earlier. Save off hp so that we can return it on exit */ hp = hvc_alloc(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops, 16); if (IS_ERR(hp)) return PTR_ERR(hp); hvc_rtas_dev = hp; return 0; } device_initcall(hvc_rtas_init); /* This will happen prior to module init. There is no tty at this time? */ static int __init hvc_rtas_console_init(void) { rtascons_put_char_token = rtas_token("put-term-char"); if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; rtascons_get_char_token = rtas_token("get-term-char"); if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE) return -EIO; hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops); add_preferred_console("hvc", 0, NULL); return 0; } console_initcall(hvc_rtas_console_init); );'>space:mode:
authorBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
committerBjorn Helgaas <bhelgaas@google.com>2017-01-27 15:00:45 -0600
commit030305d69fc6963c16003f50d7e8d74b02d0a143 (patch)
tree363a4e34d199178769b7e7eeb26ea2620a55847b /fs/xfs/xfs_mount.c
parent4d191b1b63c209e37bf27938ef365244d3c41084 (diff)
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+
Diffstat (limited to 'fs/xfs/xfs_mount.c')