linux_dsm_epyc7002/arch/powerpc/include/asm/ppc-pci.h
Breno Leitao 8d3d50bf19 powerpc/eeh: Fix a bug when pci structure is null
During a EEH recover, the pci_dev structure can be null, mainly if an
eeh event is detected during cpi config operation. In this case, the
pci_dev will not be known (and will be null) the kernel will crash
with the following message:

Unable to handle kernel paging request for data at address 0x000000a0
Faulting instruction address: 0xc00000000006b8b4
Oops: Kernel access of bad area, sig: 11 [#1]

NIP [c00000000006b8b4] .eeh_event_handler+0x10c/0x1a0
LR [c00000000006b8a8] .eeh_event_handler+0x100/0x1a0
Call Trace:
[c0000003a80dff00] [c00000000006b8a8] .eeh_event_handler+0x100/0x1a0
[c0000003a80dff90] [c000000000031f1c] .kernel_thread+0x54/0x70

The bug occurs because pci_name() tries to access a null pointer.
This patch just guarantee that pci_name() is not called on Null pointers.

Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-02-17 14:02:47 +11:00

154 lines
4.6 KiB
C

/*
* c 2001 PPC 64 Team, IBM Corp
*
* 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.
*/
#ifndef _ASM_POWERPC_PPC_PCI_H
#define _ASM_POWERPC_PPC_PCI_H
#ifdef __KERNEL__
#ifdef CONFIG_PCI
#include <linux/pci.h>
#include <asm/pci-bridge.h>
extern unsigned long isa_io_base;
extern void pci_setup_phb_io(struct pci_controller *hose, int primary);
extern void pci_setup_phb_io_dynamic(struct pci_controller *hose, int primary);
extern struct list_head hose_list;
extern void find_and_init_phbs(void);
extern struct pci_dev *isa_bridge_pcidev; /* may be NULL if no ISA bus */
/** Bus Unit ID macros; get low and hi 32-bits of the 64-bit BUID */
#define BUID_HI(buid) ((buid) >> 32)
#define BUID_LO(buid) ((buid) & 0xffffffff)
/* PCI device_node operations */
struct device_node;
typedef void *(*traverse_func)(struct device_node *me, void *data);
void *traverse_pci_devices(struct device_node *start, traverse_func pre,
void *data);
extern void pci_devs_phb_init(void);
extern void pci_devs_phb_init_dynamic(struct pci_controller *phb);
/* From rtas_pci.h */
extern void init_pci_config_tokens (void);
extern unsigned long get_phb_buid (struct device_node *);
extern int rtas_setup_phb(struct pci_controller *phb);
extern unsigned long pci_probe_only;
/* ---- EEH internal-use-only related routines ---- */
#ifdef CONFIG_EEH
void pci_addr_cache_insert_device(struct pci_dev *dev);
void pci_addr_cache_remove_device(struct pci_dev *dev);
void pci_addr_cache_build(void);
struct pci_dev *pci_get_device_by_addr(unsigned long addr);
/**
* eeh_slot_error_detail -- record and EEH error condition to the log
* @pdn: pci device node
* @severity: EEH_LOG_TEMP_FAILURE or EEH_LOG_PERM_FAILURE
*
* Obtains the EEH error details from the RTAS subsystem,
* and then logs these details with the RTAS error log system.
*/
#define EEH_LOG_TEMP_FAILURE 1
#define EEH_LOG_PERM_FAILURE 2
void eeh_slot_error_detail (struct pci_dn *pdn, int severity);
/**
* rtas_pci_enable - enable IO transfers for this slot
* @pdn: pci device node
* @function: either EEH_THAW_MMIO or EEH_THAW_DMA
*
* Enable I/O transfers to this slot
*/
#define EEH_THAW_MMIO 2
#define EEH_THAW_DMA 3
int rtas_pci_enable(struct pci_dn *pdn, int function);
/**
* rtas_set_slot_reset -- unfreeze a frozen slot
* @pdn: pci device node
*
* Clear the EEH-frozen condition on a slot. This routine
* does this by asserting the PCI #RST line for 1/8th of
* a second; this routine will sleep while the adapter is
* being reset.
*
* Returns a non-zero value if the reset failed.
*/
int rtas_set_slot_reset (struct pci_dn *);
int eeh_wait_for_slot_status(struct pci_dn *pdn, int max_wait_msecs);
/**
* eeh_restore_bars - Restore device configuration info.
* @pdn: pci device node
*
* A reset of a PCI device will clear out its config space.
* This routines will restore the config space for this
* device, and is children, to values previously obtained
* from the firmware.
*/
void eeh_restore_bars(struct pci_dn *);
/**
* rtas_configure_bridge -- firmware initialization of pci bridge
* @pdn: pci device node
*
* Ask the firmware to configure all PCI bridges devices
* located behind the indicated node. Required after a
* pci device reset. Does essentially the same hing as
* eeh_restore_bars, but for brdges, and lets firmware
* do the work.
*/
void rtas_configure_bridge(struct pci_dn *);
int rtas_write_config(struct pci_dn *, int where, int size, u32 val);
int rtas_read_config(struct pci_dn *, int where, int size, u32 *val);
/**
* eeh_mark_slot -- set mode flags for pertition endpoint
* @pdn: pci device node
*
* mark and clear slots: find "partition endpoint" PE and set or
* clear the flags for each subnode of the PE.
*/
void eeh_mark_slot (struct device_node *dn, int mode_flag);
void eeh_clear_slot (struct device_node *dn, int mode_flag);
/**
* find_device_pe -- Find the associated "Partiationable Endpoint" PE
* @pdn: pci device node
*/
struct device_node * find_device_pe(struct device_node *dn);
void eeh_sysfs_add_device(struct pci_dev *pdev);
void eeh_sysfs_remove_device(struct pci_dev *pdev);
static inline const char *eeh_pci_name(struct pci_dev *pdev)
{
return pdev ? pci_name(pdev) : "<null>";
}
#endif /* CONFIG_EEH */
#else /* CONFIG_PCI */
static inline void find_and_init_phbs(void) { }
static inline void init_pci_config_tokens(void) { }
#endif /* !CONFIG_PCI */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_PPC_PCI_H */