summaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2010-05-21powerpc/numa: Set a smaller value for RECLAIM_DISTANCE to enable zone reclaimAnton Blanchard
I noticed /proc/sys/vm/zone_reclaim_mode was 0 on a ppc64 NUMA box. It gets enabled via this: /* * If another node is sufficiently far away then it is better * to reclaim pages in a zone before going off node. */ if (distance > RECLAIM_DISTANCE) zone_reclaim_mode = 1; Since we use the default value of 20 for REMOTE_DISTANCE and 20 for RECLAIM_DISTANCE it never kicks in. The local to remote bandwidth ratios can be quite large on System p machines so it makes sense for us to reclaim clean pagecache locally before going off node. The patch below sets a smaller value for RECLAIM_DISTANCE and thus enables zone reclaim. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc: Use smt_snooze_delay=-1 to always busy loopAnton Blanchard
Right now if we want to busy loop and not give up any time to the hypervisor we put a very large value into smt_snooze_delay. This is sometimes useful when running a single partition and you want to avoid any latencies due to the hypervisor or CPU power state transitions. While this works, it's a bit ugly - how big a number is enough now we have NO_HZ and can be idle for a very long time. The patch below makes smt_snooze_delay signed, and a negative value means loop forever: echo -1 > /sys/devices/system/cpu/cpu0/smt_snooze_delay This change shouldn't affect the existing userspace tools (eg ppc64_cpu), but I'm cc-ing Nathan just to be sure. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc: Remove check of ibm,smt-snooze-delay OF propertyAnton Blanchard
I'm not sure why we have code for parsing an ibm,smt-snooze-delay OF property. Since we have a smt-snooze-delay= boot option and we can also set it at runtime via sysfs, it should be safe to get rid of this code. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/kdump: Fix race in kdump shutdownMichael Neuling
When we are crashing, the crashing/primary CPU IPIs the secondaries to turn off IRQs, go into real mode and wait in kexec_wait. While this is happening, the primary tears down all the MMU maps. Unfortunately the primary doesn't check to make sure the secondaries have entered real mode before doing this. On PHYP machines, the secondaries can take a long time shutting down the IRQ controller as RTAS calls are need. These RTAS calls need to be serialised which resilts in the secondaries contending in lock_rtas() and hence taking a long time to shut down. We've hit this on large POWER7 machines, where some secondaries are still waiting in lock_rtas(), when the primary tears down the HPTEs. This patch makes sure all secondaries are in real mode before the primary tears down the MMU. It uses the new kexec_state entry in the paca. It times out if the secondaries don't reach real mode after 10sec. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/kexec: Fix race in kexec shutdownMichael Neuling
In kexec_prepare_cpus, the primary CPU IPIs the secondary CPUs to kexec_smp_down(). kexec_smp_down() calls kexec_smp_wait() which sets the hw_cpu_id() to -1. The primary does this while leaving IRQs on which means the primary can take a timer interrupt which can lead to the IPIing one of the secondary CPUs (say, for a scheduler re-balance) but since the secondary CPU now has a hw_cpu_id = -1, we IPI CPU -1... Kaboom! We are hitting this case regularly on POWER7 machines. There is also a second race, where the primary will tear down the MMU mappings before knowing the secondaries have entered real mode. Also, the secondaries are clearing out any pending IPIs before guaranteeing that no more will be received. This changes kexec_prepare_cpus() so that we turn off IRQs in the primary CPU much earlier. It adds a paca flag to say that the secondaries have entered the kexec_smp_down() IPI and turned off IRQs, rather than overloading hw_cpu_id with -1. This new paca flag is again used to in indicate when the secondaries has entered real mode. It also ensures that all CPUs have their IRQs off before we clear out any pending IPI requests (in kexec_cpu_down()) to ensure there are no trailing IPIs left unacknowledged. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/kexec: Speedup kexec hash PTE tear downMichael Neuling
Currently for kexec the PTE tear down on 1TB segment systems normally requires 3 hcalls for each PTE removal. On a machine with 32GB of memory it can take around a minute to remove all the PTEs. This optimises the path so that we only remove PTEs that are valid. It also uses the read 4 PTEs at once HCALL. For the common case where a PTEs is invalid in a 1TB segment, this turns the 3 HCALLs per PTE down to 1 HCALL per 4 PTEs. This gives an > 10x speedup in kexec times on PHYP, taking a 32GB machine from around 1 minute down to a few seconds. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/pseries: Add hcall to read 4 ptes at a time in real modeMichael Neuling
This adds plpar_pte_read_4_raw() which can be used read 4 PTEs from PHYP at a time, while in real mode. It also creates a new hcall9 which can be used in real mode. It's the same as plpar_hcall9 but minus the tracing hcall statistics which may require variables outside the RMO. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc: Use more accurate limit for first segment memory allocationsAnton Blanchard
Author: Milton Miller <miltonm@bga.com> On large machines we are running out of room below 256MB. In some cases we only need to ensure the allocation is in the first segment, which may be 256MB or 1TB. Add slb0_limit and use it to specify the upper limit for the irqstack and emergency stacks. On a large ppc64 box, this fixes a panic at boot when the crashkernel= option is specified (previously we would run out of memory below 256MB). Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/kdump: Use chip->shutdown to disable IRQsAnton Blanchard
I saw this in a kdump kernel: IOMMU table initialized, virtual merging enabled Interrupt 155954 (real) is invalid, disabling it. Interrupt 155953 (real) is invalid, disabling it. ie we took some spurious interrupts. default_machine_crash_shutdown tries to disable all interrupt sources but uses chip->disable which maps to the default action of: static void default_disable(unsigned int irq) { } If we use chip->shutdown, then we actually mask the IRQ: static void default_shutdown(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); desc->chip->mask(irq); desc->status |= IRQ_MASKED; } Not sure why we don't implement a ->disable action for xics.c, or why default_disable doesn't mask the interrupt. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/kdump: CPUs assume the context of the oopsing CPUAnton Blanchard
We wrap the crash_shutdown_handles[] calls with longjmp/setjmp, so if any of them fault we can recover. The problem is we add a hook to the debugger fault handler hook which calls longjmp unconditionally. This first part of kdump is run before we marshall the other CPUs, so there is a very good chance some CPU on the box is going to page fault. And when it does it hits the longjmp code and assumes the context of the oopsing CPU. The machine gets very confused when it has 10 CPUs all with the same stack, all thinking they have the same CPU id. I get even more confused trying to debug it. The patch below adds crash_shutdown_cpu and uses it to specify which cpu is in the protected region. Since it can only be -1 or the oopsing CPU, we don't need to use memory barriers since it is only valid on the local CPU - no other CPU will ever see a value that matches it's local CPU id. Eventually we should switch the order and marshall all CPUs before doing the crash_shutdown_handles[] calls, but that is a bigger fix. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/crashdump: Do not fail on NULL pointer dereferencingMaxim Uvarov
Signed-off-by: Maxim Uvarov <muvarov@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/eeh: Fix oops when probing in early bootAnton Blanchard
If we take an EEH error early enough, we oops: Call Trace: [c000000010483770] [c000000000013ee4] .show_stack+0xd8/0x218 (unreliable) [c000000010483850] [c000000000658940] .dump_stack+0x28/0x3c [c0000000104838d0] [c000000000057a68] .eeh_dn_check_failure+0x2b8/0x304 [c000000010483990] [c0000000000259c8] .rtas_read_config+0x120/0x168 [c000000010483a40] [c000000000025af4] .rtas_pci_read_config+0xe4/0x124 [c000000010483af0] [c00000000037af18] .pci_bus_read_config_word+0xac/0x104 [c000000010483bc0] [c0000000008fec98] .pcibios_allocate_resources+0x7c/0x220 [c000000010483c90] [c0000000008feed8] .pcibios_resource_survey+0x9c/0x418 [c000000010483d80] [c0000000008fea10] .pcibios_init+0xbc/0xf4 [c000000010483e20] [c000000000009844] .do_one_initcall+0x98/0x1d8 [c000000010483ed0] [c0000000008f0560] .kernel_init+0x228/0x2e8 [c000000010483f90] [c000000000031a08] .kernel_thread+0x54/0x70 EEH: Detected PCI bus error on device <null> EEH: This PCI device has failed 1 times in the last hour: EEH: location=U78A5.001.WIH8464-P1 driver= pci addr=0001:00:01.0 EEH: of node=/pci@800000020000209/usb@1 EEH: PCI device/vendor: 00351033 EEH: PCI cmd/status register: 12100146 Unable to handle kernel paging request for data at address 0x00000468 Oops: Kernel access of bad area, sig: 11 [#1] .... NIP [c000000000057610] .rtas_set_slot_reset+0x38/0x10c LR [c000000000058724] .eeh_reset_device+0x5c/0x124 Call Trace: [c00000000bc6bd00] [c00000000005a0e0] .pcibios_remove_pci_devices+0x7c/0xb0 (unreliable) [c00000000bc6bd90] [c000000000058724] .eeh_reset_device+0x5c/0x124 [c00000000bc6be40] [c0000000000589c0] .handle_eeh_events+0x1d4/0x39c [c00000000bc6bf00] [c000000000059124] .eeh_event_handler+0xf0/0x188 [c00000000bc6bf90] [c000000000031a08] .kernel_thread+0x54/0x70 We called rtas_set_slot_reset while scanning the bus and before the pci_dn to pcidev mapping has been created. Since we only need the pcidev to work out the type of reset and that only gets set after the module for the device loads, lets just do a hot reset if the pcidev is NULL. Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Linas Vepstas <linasvepstas@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/pci: Check devices status property when scanning OF treeSonny Rao
We ran into an issue where it looks like we're not properly ignoring a pci device with a non-good status property when we walk the device tree and instanciate the Linux side PCI devices. However, the EEH init code does look for the property and disables EEH on these devices. This leaves us in an inconsistent where we are poking at a supposedly bad piece of hardware and RTAS will block our config cycles because EEH isn't enabled anyway. Signed-of-by: Sonny Rao <sonnyrao@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/vio: Switch VIO Bus PM to use generic helpersBrian King
Switch to use the generic power management helpers. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc: Avoid bad relocations in iSeries codePaul Mackerras
Subrata Modak reported that building a CONFIG_RELOCATABLE kernel with CONFIG_ISERIES enabled gives the following warnings: WARNING: 4 bad relocations c00000000007216e R_PPC64_ADDR16_HIGHEST __ksymtab+0x00000000009dcec8 c000000000072172 R_PPC64_ADDR16_HIGHER __ksymtab+0x00000000009dcec8 c00000000007217a R_PPC64_ADDR16_HI __ksymtab+0x00000000009dcec8 c00000000007217e R_PPC64_ADDR16_LO __ksymtab+0x00000000009dcec8 The reason is that decrementer_iSeries_masked is using LOAD_REG_IMMEDIATE to get the address of a kernel symbol, which creates relocations that aren't handled by the kernel relocator code. Instead of reading the tb_ticks_per_jiffy variable, we can just set the decrementer to its maximum value (0x7fffffff) and that will work just as well. In fact timer_interrupt sets the decrementer to that value initially anyway, and we are sure to get into timer_interrupt once interrupts are reenabled because we store 1 to the decrementer interrupt flag in the lppaca (LPPACADECRINT(r12) here). Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc: Use common cpu_die (fixes SMP+SUSPEND build)Milton Miller
Configuring a powerpc 32 bit kernel for both SMP and SUSPEND turns on CPU_HOTPLUG to enable disable_nonboot_cpus to be called by the common suspend code. Previously the definition of cpu_die for ppc32 was in the powermac platform code, causing it to be undefined if that platform as not selected. arch/powerpc/kernel/built-in.o: In function 'cpu_idle': arch/powerpc/kernel/idle.c:98: undefined reference to 'cpu_die' Move the code from setup_64 to smp.c and rename the power mac versions to their specific names. Note that this does not setup the cpu_die pointers in either smp_ops (request a given cpu die) or ppc_md (make this cpu die), for other platforms but there are generic versions in smp.c. Reported-by: Matt Sealey <matt@genesi-usa.com> Reported-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Anton Vorontsov <avorontsov@mvista.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc: Fix string library functionsAndreas Schwab
The powerpc strncmp implementation does not correctly handle a zero length, despite the claim in 0119536cd314ef95553604208c25bc35581f7f0a (Add hand-coded assembly strcmp). Additionally, all the length arguments are size_t, not int, so use PPC_LCMPI and eq instead of cmpwi and le throughout. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21powerpc/rtasd: Don't start event scan if scan rate is zeroMichael Ellerman
There appear to be Pegasos systems which have the rtas-event-scan RTAS tokens, but on which the event scan always fails. They also have an event-scan-rate property containing 0, which means call event scan 0 times per minute. So interpret a scan rate of 0 to mean don't scan at all. This fixes the problem on the Pegasos machines and makes sense as well. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-21drm/radeon/kms/pm/r600: select the mid clock mode for single head low profileAlex Deucher
This saves some more power at the expense of performance. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-21Merge remote branch 'nouveau/for-airlied' into drm-nextDave Airlie
* nouveau/for-airlied: drm/nouveau: fix i2c-related init table handlers drm/nouveau: support init table i2c device identifier 0x81 drm/nouveau: ensure we've parsed i2c table entry for INIT_*I2C* handlers drm/nouveau: display error message for any failed init table opcode drm/nouveau: fix init table handlers to return proper error codes drm/nv50: support fractional feedback divider on newer chips drm/nv50: fix monitor detection on certain chipsets drm/nv50: store full dcb i2c entry from vbios drm/nv50: fix suspend/resume with DP outputs drm/nv50: output calculated crtc pll when debugging on drm/nouveau: dump pll limits entries when debugging is on drm/nouveau: bios parser fixes for eDP boards drm/nouveau: fix a nouveau_bo dereference after it's been destroyed drm/nv40: remove some completed ctxprog TODOs drm/nv04: Implement missing nv04 PGRAPH methods in software. drm/nouveau: Use 0x5f instead of 0x9f as imageblit on original NV10.
2010-05-21drm/radeon: fix power supply kconfig interaction.Dave Airlie
radeon needs power supply to get correct PM info so select it at the radeon level not at the kms option. Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-21drm/radeon/kms: record object that have been list reservedJerome Glisse
list reservation was too optimistic about ttm object reservation and could think that an object reserved by some other process as reserved by the list reservation which was false. Thus when unreserving the list it might unreserve object that it didn't reserved in the list. Sorry if it's hard to follow but this kind of things are just causing headheck. Signed-off-by: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-21drm/radeon: AGP memory is only I/O if the aperture can be mapped by the CPU.Michel Dänzer
Fixes AGP initialization failure with Apple UniNorth bridges due to trying to ioremap() normal RAM. Signed-off-by: Michel Dänzer <daenzer@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-21drm/radeon/kms: don't default display priority to high on rs4xxAlex Deucher
Seems to cause issues with the sound hardware. Fixes kernel bug 15982: https://bugzilla.kernel.org/show_bug.cgi?id=15982 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-21drm/edid: fix typo in 1600x1200@75 modeAlex Deucher
Spotted by Scott Bertilson. Fixes fdo bug 28146. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Reviewed-by: Mark Marshall <mark.marshall@csr.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (229 commits) USB: remove unused usb_buffer_alloc and usb_buffer_free macros usb: musb: update gfp/slab.h includes USB: ftdi_sio: fix legacy SIO-device header USB: kl5usb105: reimplement using generic framework USB: kl5usb105: minor clean ups USB: kl5usb105: fix memory leak USB: io_ti: use kfifo to implement write buffering USB: io_ti: remove unsused private counter USB: ti_usb: use kfifo to implement write buffering USB: ir-usb: fix incorrect write-buffer length USB: aircable: fix incorrect write-buffer length USB: safe_serial: straighten out read processing USB: safe_serial: reimplement read using generic framework USB: safe_serial: reimplement write using generic framework usb-storage: always print quirks USB: usb-storage: trivial debug improvements USB: oti6858: use port write fifo USB: oti6858: use kfifo to implement write buffering USB: cypress_m8: use kfifo to implement write buffering USB: cypress_m8: remove unused drain define ... Fix up conflicts (due to usb_buffer_alloc/free renaming) in drivers/input/tablet/acecad.c drivers/input/tablet/kbtab.c drivers/input/tablet/wacom_sys.c drivers/media/video/gspca/gspca.c sound/usb/usbaudio.c
2010-05-20sound: fixup for usb_buffer_alloc/free renameStephen Rothwell
This is needed before the USB merge. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1674 commits) qlcnic: adding co maintainer ixgbe: add support for active DA cables ixgbe: dcb, do not tag tc_prio_control frames ixgbe: fix ixgbe_tx_is_paused logic ixgbe: always enable vlan strip/insert when DCB is enabled ixgbe: remove some redundant code in setting FCoE FIP filter ixgbe: fix wrong offset to fc_frame_header in ixgbe_fcoe_ddp ixgbe: fix header len when unsplit packet overflows to data buffer ipv6: Never schedule DAD timer on dead address ipv6: Use POSTDAD state ipv6: Use state_lock to protect ifa state ipv6: Replace inet6_ifaddr->dead with state cxgb4: notify upper drivers if the device is already up when they load cxgb4: keep interrupts available when the ports are brought down cxgb4: fix initial addition of MAC address cnic: Return SPQ credit to bnx2x after ring setup and shutdown. cnic: Convert cnic_local_flags to atomic ops. can: Fix SJA1000 command register writes on SMP systems bridge: fix build for CONFIG_SYSFS disabled ARCNET: Limit com20020 PCI ID matches for SOHARD cards ... Fix up various conflicts with pcmcia tree drivers/net/ {pcmcia/3c589_cs.c, wireless/orinoco/orinoco_cs.c and wireless/orinoco/spectrum_cs.c} and feature removal (Documentation/feature-removal-schedule.txt). Also fix a non-content conflict due to pm_qos_requirement getting renamed in the PM tree (now pm_qos_request) in net/mac80211/scan.c
2010-05-20echi-dbgp: Add kernel debugger support for the usb debug portJason Wessel
This patch adds the capability to use the usb debug port with the kernel debugger. It is also still possible to use this functionality with or without the earlyprintk=dbgpX. It is possible to use the kgdbwait boot argument to debug very early in the kernel start up code. There are two ways to use this driver extension with a kernel boot argument. 1) kgdbdbgp=# -- Where # is the number of the usb debug controller You must use sysrq-g to break into the kernel debugger on another connection type other than the dbgp. 2) kgdbdbgp=#debugControlNum#,#Seconds# In this mode, the usb debug port is polled every #Seconds# for character input. It is possible to use gdb or press control-c to break into the kernel debugger. From the implementation perspective there are 3 high level changes. 1) Allow variable retries for the the hardware via dbgp_bulk_read(). The amount of retries for the dbgp_bulk_read() needed to be variable instead of fixed. We do not want to poll at all when the kernel is operating in interrupt driven mode. The polling only occurs if the kernel was booted when specifying some number of seconds via the kgdbdbgp boot argument (IE kgdbdbgp=0,1). In this case the loop count is reduced to 1 so as introduce the smallest amount of latency as possible. 2) Save the bulk IN endpoint address for use by the kgdb code. 3) The addition of the kgdb interface code. This consisted of adding in a character read function for the dbgp as well as a polling thread to allow the dbgp to interrupt the kernel execution. The rest is the typical kgdb I/O api. CC: Eric Biederman <ebiederm@xmission.com> CC: Yinghai Lu <yhlu.kernel@gmail.com> CC: linux-usb@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-20earlyprintk,vga,kdb: Fix \b and \r for earlyprintk=vga with kdbJason Wessel
Allow kdb to work properly with with earlyprintk=vga by interpreting the backspace and carriage return output characters. These interpretation of these characters is used for simple line editing provided in the kdb shell. CC: Thomas Gleixner <tglx@linutronix.de> CC: Ingo Molnar <mingo@redhat.com> CC: H. Peter Anvin <hpa@zytor.com> CC: x86@kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdboc: Add ekgdboc for early use of the kernel debuggerJason Wessel
The ekgdboc= differs from kgdboc= in that you can begin debuggin as soon as the exceptions are setup and the kgdb I/O driver is available, instead of waiting until the tty subsystem is available. CC: kgdb-bugreport@lists.sourceforge.net Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20x86,early dr regs,kgdb: Allow kernel debugger early dr register accessJason Wessel
If the kernel debugger was configured, attached and started with kgdbwait, the hardware breakpoint registers should get restored by the kgdb code which is managing the dr registers. CC: x86@kernel.org CC: Thomas Gleixner <tglx@linutronix.de> CC: Ingo Molnar <mingo@redhat.com> CC: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20x86,kgdb: Implement early hardware breakpoint debuggingJason Wessel
It is not possible to use the hw_breakpoint.c API prior to mm_init(), but it is possible to use hardware breakpoints with the kernel debugger. Prior to smp_init() it is possible to simply write to the dr registers of the boot cpu directly. This can be used up until the kgdb_arch_late() is invoked, at which point the standard hw_breakpoint.c API will get used. CC: Frederic Weisbecker <fweisbec@gmail.com> CC: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20x86, kgdb, init: Add early and late debug statesJason Wessel
The kernel debugger can operate well before mm_init(), but the x86 hardware breakpoint code which uses the perf api requires that the kernel allocators are initialized. This means the kernel debug core needs to provide an optional arch specific call back to allow the initialization functions to run after the kernel has been further initialized. The kdb shell already had a similar restriction with an early initialization and late initialization. The kdb_init() was moved into the debug core's version of the late init which is called dbg_late_init(); CC: kgdb-bugreport@lists.sourceforge.net Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20x86, kgdb: early trap init for early debugJan Kiszka
Allow the x86 arch to have early exception processing for the purpose of debugging via the kgdb. Signed-off-by: Jan Kiszka <jan.kiszka@web.de> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kdb,debug_core: Allow the debug core to receive a panic notificationJason Wessel
It is highly desirable to trap into kdb on panic. The debug core will attempt to register as the first in line for the panic notifier. CC: Ingo Molnar <mingo@elte.hu> CC: Andrew Morton <akpm@linux-foundation.org> CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20MAINTAINERS: update kgdb, kdb, and debug_core infoJason Wessel
Update the maintained files sections. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20debug_core,kdb: Allow the debug core to process a recursive debug entryJason Wessel
This allows kdb to debug a crash with in the kms code with a single level recursive re-entry. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20printk,kdb: capture printk() when in kdb shellJason Wessel
Certain calls from the kdb shell will call out to printk(), and any of these calls should get vectored back to the kdb_printf() so that the kdb pager and processing can be used, as well as to properly channel I/O to the polled I/O devices. CC: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Andrew Morton <akpm@linux-foundation.org>
2010-05-20kgdboc,kdb: Allow kdb to work on a non open console portJason Wessel
If kdb is open on a serial port that is not actually a console make sure to call the poll routines to emit and receive characters. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Martin Hicks <mort@sgi.com>
2010-05-20kgdb: Add the ability to schedule a breakpoint via a taskletJason Wessel
Some kgdb I/O modules require the ability to create a breakpoint tasklet, such as kgdboc and external modules such as kgdboe. The breakpoint tasklet is used as an asynchronous entry point into the debugger which will have a different function scope than the current execution path where it might not be safe to have an inline breakpoint. This is true of some of the kgdb I/O drivers which share code with kgdb and rest of the kernel users. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20mips,kgdb: kdb low level trap catch and stack traceJason Wessel
The only way the debugger can handle a trap in inside rcu_lock, notify_die, or atomic_notifier_call_chain without a recursive fault is to have a low level "first opportunity handler" do_trap_or_bp() handler. Generally this will be something the vast majority of folks will not need, but for those who need it, it is added as a kernel .config option called KGDB_LOW_LEVEL_TRAP. Also added was a die notification for oops such that kdb can catch an oops for analysis. There appeared to be no obvious way to pass the struct pt_regs from the original exception back to the stack back tracer, so a special case was added to show_stack() for when kdb is active because you generally desire to generally look at the back trace of the original exception. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Ralf Baechle <ralf@linux-mips.org>
2010-05-20powerpc,kgdb: Introduce low level trap catchingJason Wessel
The only way the debugger can handle a trap in inside rcu_lock, notify_die, or atomic_notifier_call_chain without a recursive fault is to allow the kernel debugger to handle the exception first in program_check_exception(). The other change here is to make sure that kgdb_handle_exception() is called with correct parameters when catching an oops, because kdb needs to know if the entry was an oops, single step, or breakpoint exception. [benh@kernel.crashing.org: move debugger_bpt instead of #ifdef] CC: Paul Mackerras <paulus@samba.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-20x86,kgdb: Add low level debug hookJason Wessel
The only way the debugger can handle a trap in inside rcu_lock, notify_die, or atomic_notifier_call_chain without a triple fault is to have a low level "first opportunity handler" in the int3 exception handler. Generally this will be something the vast majority of folks will not need, but for those who need it, it is added as a kernel .config option called KGDB_LOW_LEVEL_TRAP. CC: Ingo Molnar <mingo@elte.hu> CC: Thomas Gleixner <tglx@linutronix.de> CC: H. Peter Anvin <hpa@zytor.com> CC: x86@kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdb: remove post_primary_code referencesJason Wessel
Remove all the references to the kgdb_post_primary_code. This function serves no useful purpose because you can obtain the same information from the "struct kgdb_state *ks" from with in the debugger, if for some reason you want the data. Also remove the unintentional duplicate assignment for ks->ex_vector. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdb,docs: Update the kgdb docs to include kdbJason Wessel
Update the kgdb docs to reflect the new directory structure and API. Merge in the kdb shell information. [Randy Dunlap <rdunlap@xenotime.net>: grammatical corrections] CC: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20kgdboc,keyboard: Keyboard driver for kdb with kgdbJason Wessel
This patch adds in the kdb PS/2 keyboard driver. This was mostly a direct port from the original kdb where I cleaned up the code against checkpatch.pl and added the glue to stitch it into kgdb. This patch also enables early kdb debug via kgdbwait and the keyboard. All the access to configure kdb using either a serial console or the keyboard is done via kgdboc. If you want to use only the keyboard and want to break in early you would add to your kernel command arguments: kgdboc=kbd kgdbwait If you wanted serial and or the keyboard access you could use: kgdboc=kbd,ttyS0 You can also configure kgdboc as a kernel module or at run time with the sysfs where you can activate and deactivate kgdb. Turn it on: echo kbd,ttyS0 > /sys/module/kgdboc/parameters/kgdboc Turn it off: echo "" > /sys/module/kgdboc/parameters/kgdboc Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2010-05-20kgdb: gdb "monitor" -> kdb passthroughJason Wessel
One of the driving forces behind integrating another front end (kdb) to the debug core is to allow front end commands to be accessible via gdb's monitor command. It is true that you could write gdb macros to get certain data, but you may want to just use gdb to access the commands that are available in the kdb front end. This patch implements the Rcmd gdb stub packet. In gdb you access this with the "monitor" command. For instance you could type "monitor help", "monitor lsmod" or "monitor ps A" etc... There is no error checking or command restrictions on what you can and cannot access at this point. Doing something like trying to set breakpoints with the monitor command is going to cause nothing but problems. Perhaps in the future only the commands that are actually known to work with the gdb monitor command will be available. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-05-20sparc,sunzilog: Add console polling support for sunzilog serial driverJason Wessel
Allow kgdboc to work on sparc hardware with the Zilog serial chips. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: David S. Miller <davem@davemloft.net>
2010-05-20sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console codeJason Wessel
The sci_poll_get_char() needs to return immediately if there is no input from the chip to process, and must return a value of NO_POLL_CHAR. This allows kgdboc to process multiple polled devices while kgdb is active. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Paul Mundt <lethal@linux-sh.org>