Currently, when CONFIG_VIRT_CPU_ACCOUNTING is enabled, we use the
PURR register for measuring the user and system time used by
processes, as well as other related times such as hardirq and
softirq times. This turns out to be quite confusing for users
because it means that a program will often be measured as taking
less time when run on a multi-threaded processor (SMT2 or SMT4 mode)
than it does when run on a single-threaded processor (ST mode), even
though the program takes longer to finish. The discrepancy is
accounted for as stolen time, which is also confusing, particularly
when there are no other partitions running.
This changes the accounting to use the timebase instead, meaning that
the reported user and system times are the actual number of real-time
seconds that the program was executing on the processor thread,
regardless of which SMT mode the processor is in. Thus a program will
generally show greater user and system times when run on a
multi-threaded processor than on a single-threaded processor.
On pSeries systems on POWER5 or later processors, we measure the
stolen time (time when this partition wasn't running) using the
hypervisor dispatch trace log. We check for new entries in the
log on every entry from user mode and on every transition from
kernel process context to soft or hard IRQ context (i.e. when
account_system_vtime() gets called). So that we can correctly
distinguish time stolen from user time and time stolen from system
time, without having to check the log on every exit to user mode,
we store separate timestamps for exit to user mode and entry from
user mode.
On systems that have a SPURR (POWER6 and POWER7), we read the SPURR
in account_system_vtime() (as before), and then apportion the SPURR
ticks since the last time we read it between scaled user time and
scaled system time according to the relative proportions of user
time and system time over the same interval. This avoids having to
read the SPURR on every kernel entry and exit. On systems that have
PURR but not SPURR (i.e., POWER5), we do the same using the PURR
rather than the SPURR.
This disables the DTL user interface in /sys/debug/kernel/powerpc/dtl
for now since it conflicts with the use of the dispatch trace log
by the time accounting code.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This arranges for the lppaca structs for most cpus to be dynamically
allocated in the same manner as the paca structs. If we don't include
support for legacy iSeries, only the first lppaca is statically
allocated; the rest are dynamically allocated. If we include legacy
iSeries support, then we statically allocate the first 64 lppaca
structs, since the iSeries hypervisor requires that the lppaca
structs be present in the data section of the kernel image, but
legacy iSeries supports at most 64 cpus.
With CONFIG_NR_CPUS, the kernel image size for a typical pSeries config
went from:
text data bss dec hex filename
9524478 4734564 8469944 22728986 15ad11a ../test-1024/vmlinux
to:
text data bss dec hex filename
9524482 3751508 8469944 21745934 14bd10e ../test-1024/vmlinux
a reduction of 983052 bytes overall.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently we have the lppaca structs as a simple array of NR_CPUS
entries, taking up space in the data section of the kernel image.
In future we would like to allocate them dynamically, so this
abstracts out the accesses to the array, making it easier to
change how we locate the lppaca for a given cpu in future.
Specifically, lppaca[cpu] changes to lppaca_of(cpu).
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Simple cleanup by moving arch_sd_sibling_asym_packing from process.c to
smp.c to save an #ifdef CONFIG_SMP
No functionality change.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add a check for the stack canary when we oops, similar to x86. This should make
it clear that we overran our stack:
Unable to handle kernel paging request for data at address 0x24652f63700ac689
Faulting instruction address: 0xc000000000063d24
Thread overran stack, or stack corrupted
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The POWER architecture does not require stcx to check that it is operating
on the same address as the larx. This means it is possible for an
an exception handler to execute a larx, get a reservation, decide
not to do the stcx and then return back with an active reservation. If the
interrupted code was in the middle of a larx/stcx sequence the stcx could
incorrectly succeed.
All recent POWER CPUs check the address before letting the stcx succeed
so we can create a CPU feature and nop it out. As Ben suggested, we can
only do this in our syscall path because there is a remote possibility
some kernel code gets interrupted by an exception that ends up operating
on the same cacheline.
Thanks to Paul Mackerras and Derek Williams for the idea.
To test this I used a very simple null syscall (actually getppid) testcase
at http://ozlabs.org/~anton/junkcode/null_syscall.c
I tested against 2.6.35-git10 with the following changes against the
pseries_defconfig:
CONFIG_VIRT_CPU_ACCOUNTING=n
CONFIG_AUDIT=n
CONFIG_PPC_4K_PAGES=n
CONFIG_PPC_64K_PAGES=y
CONFIG_FORCE_MAX_ZONEORDER=9
CONFIG_PPC_SUBPAGE_PROT=n
CONFIG_FUNCTION_TRACER=n
CONFIG_FUNCTION_GRAPH_TRACER=n
CONFIG_IRQSOFF_TRACER=n
CONFIG_STACK_TRACER=n
to remove the overhead of virtual CPU accounting, syscall auditing and
the ftrace mcount tracers. 64kB pages were enabled to minimise TLB misses.
POWER6: +8.2%
POWER7: +7.0%
Another suggestion was to use a larx to something in the L1 instead of a stcx.
This was almost as fast as removing the larx on POWER6, but only 3.5% faster
on POWER7. We can use this to speed up the reservation clear in our
exception exit code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds the equivalent of csum_and_copy_from_user for the receive side so we
can copy and checksum in one pass. It is modelled on the generic checksum
routine.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We use the same core loop as the new csum_partial, adding in the
stores and exception handling code. To keep things simple we do all the
exception fixup in csum_and_copy_from_user. This wrapper function is
modelled on the generic checksum code and is careful to always calculate
a complete checksum even if we only copied part of the data to userspace.
To test this I forced checksumming on over loopback and ran socklib (a
simple TCP benchmark). On a POWER6 575 throughput improved by 19% with
this patch. If I forced both the sender and receiver onto the same cpu
(with the hope of shifting the benchmark from being cache bandwidth limited
to cpu limited), adding this patch improved performance by 55%
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The main loop of csum_partial runs very slowly on recent POWER CPUs. After some
analysis on both POWER6 and POWER7 I came up with routine below. First we get
the source aligned to a double word, ignoring any odd alignment to keep things
simple. Then we do 64 bytes at a time, with an entry and exit limb of a further
64 bytes. On both POWER6 and POWER7 this should be as fast as we can go since
we are limited by the latency of the adde instructions.
To test this I forced checksumming on over loopback and ran socklib (a
simple TCP benchmark). On a POWER6 575 throughput improved by 11% with
this patch.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The dlpar code can cause a deadlock to occur when making the RTAS
configure-connector call. This occurs because we make kmalloc calls,
which can block, while parsing the rtas_data_buf and holding the
rtas_data_buf_lock. This an cause issues if someone else attempts
to grab the rtas_data_bug_lock.
This patch alleviates this issue by copying the contents of the rtas_data_buf
to a local buffer before parsing. This allows us to only hold the
rtas_data_buf_lock around the RTAS configure-connector calls.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is needed for proper PCI-E support on P1021 SoCs.
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Add a call to of_node_put in the error handling code following a call to
of_find_compatible_node.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r exists@
local idexpression x;
expression E,E1;
statement S;
@@
*x =
(of_find_node_by_path
|of_find_node_by_name
|of_find_node_by_phandle
|of_get_parent
|of_get_next_parent
|of_get_next_child
|of_find_compatible_node
|of_match_node
)(...);
...
if (x == NULL) S
<... when != x = E
*if (...) {
... when != of_node_put(x)
when != if (...) { ... of_node_put(x); ... }
(
return <+...x...+>;
|
* return ...;
)
}
...>
of_node_put(x);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The function of_iomap returns the result of calling ioremap, so iounmap
should be called on the result in the error handling code, as done in the
normal exit of the function.
The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r exists@
local idexpression x;
expression E,E1;
identifier l;
statement S;
@@
*x = of_iomap(...);
... when != iounmap(x)
when != if (...) { ... iounmap(x); ... }
when != E = x
when any
(
if (x == NULL) S
|
if (...) {
... when != iounmap(x)
when != if (...) { ... iounmap(x); ... }
(
return <+...x...+>;
|
* return ...;
)
}
)
... when != x = E1
when any
iounmap(x);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Fixes the following compile problem on E500 platforms:
arch/powerpc/sysdev/fsl_rio.c: In function 'fsl_rio_mcheck_exception':
arch/powerpc/sysdev/fsl_rio.c:248: error: 'MCSR_MASK' undeclared (first use in this function)
Also fixes the compile problem on non-E500 platforms.
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
arch/powerpc/platforms/85xx/p1022_ds.c:22:23: error: linux/lmb.h: No such file or directory
arch/powerpc/platforms/85xx/p1022_ds.c: In function 'p1022_ds_setup_arch':
arch/powerpc/platforms/85xx/p1022_ds.c💯 error: implicit declaration of function 'memblock_end_of_DRAM'
arch/powerpc/platforms/85xx/p1022_ds.c: At top level:
arch/powerpc/platforms/85xx/p1022_ds.c:147: error: 'udbg_progress' undeclared here (not in a function)
make[2]: *** [arch/powerpc/platforms/85xx/p1022_ds.o] Error 1
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Commit 99d8238f berobbed the for_each loop of its iterator! Let's be
nice and give it back, so it compiles for us.
CC: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
In f761622e59 we changed
early_setup_secondary so it's called using the proper kernel stack
rather than the emergency one.
Unfortunately, this stack pointer can't be used when translation is off
on PHYP as this stack pointer might be outside the RMO. This results in
the following on all non zero cpus:
cpu 0x1: Vector: 300 (Data Access) at [c00000001639fd10]
pc: 000000000001c50c
lr: 000000000000821c
sp: c00000001639ff90
msr: 8000000000001000
dar: c00000001639ffa0
dsisr: 42000000
current = 0xc000000016393540
paca = 0xc000000006e00200
pid = 0, comm = swapper
The original patch was only tested on bare metal system, so it never
caught this problem.
This changes __secondary_start so that we calculate the new stack
pointer but only start using it after we've called early_setup_secondary.
With this patch, the above problem goes away.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 0fe1ac48 ("powerpc/perf_event: Fix oops due to
perf_event_do_pending call") moved the call to perf_event_do_pending
in timer_interrupt() down so that it was after the irq_enter() call.
Unfortunately this moved it after the code that checks whether it
is time for the next decrementer clock event. The result is that
the call to perf_event_do_pending() won't happen until the next
decrementer clock event is due. This was pointed out by Milton
Miller.
This fixes it by moving the check for whether it's time for the
next decrementer clock event down to the point where we're about
to call the event handler, after we've called perf_event_do_pending.
This has the side effect that on old pre-Core99 Powermacs where we
use the ppc_n_lost_interrupts mechanism to replay interrupts, a
replayed interrupt will incur a little more latency since it will
now do the code from the irq_enter down to the irq_exit, that it
used to skip. However, these machines are now old and rare enough
that this doesn't matter. To make it clear that ppc_n_lost_interrupts
is only used on Powermacs, and to speed up the code slightly on
non-Powermac ppc32 machines, the code that tests ppc_n_lost_interrupts
is now conditional on CONFIG_PMAC as well as CONFIG_PPC32.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Call kexec purgatory code correctly. We were getting lucky before.
If you examine the powerpc 32bit kexec "purgatory" code you will
see it expects the following:
>From kexec-tools: purgatory/arch/ppc/v2wrap_32.S
-> calling convention:
-> r3 = physical number of this cpu (all cpus)
-> r4 = address of this chunk (master only)
As such, we need to set r3 to the current core, r4 happens to be
unused by purgatory at the moment but we go ahead and set it
here as well
Signed-off-by: Matthew McClintock <msm@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier/blackfin:
Blackfin: bf52x/bf54x boards: drop unused nand page size
Blackfin: punt duplicate SPORT MMR defines
* 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
ARM: S5PV310: Fix on Secondary CPU startup
ARM: S5PV310: Bug fix on uclk1 and sclk_pwm
ARM: S5PV310: Fix missed uart clocks
ARM: S5PV310: Should be clk_sclk_apll not clk_mout_apll
ARM: S5PV310: Fix on PLL setting for S5PV310
ARM: S5PV310: Add CMU block for S5PV310 Clock
ARM: S5PV310: Fix on typo irqs.h of S5PV310
ARM: S5PV310: Fix on default ZRELADDR of ARCH_S5PV310
ARM: S5PV310: Fix on GPIO base addresses
ARM: SAMSUNG: Fix on build warning regarding VMALLOC_END type
ARM: S5P: VMALLOC_END should be unsigned long
* 'for-linus' of git://android.git.kernel.org/kernel/tegra:
arm: tegra: VMALLOC_END should be unsigned long
arm: tegra: fix compilation of board-harmony.c
* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
OMAP3: PM: ensure IO wakeups are properly disabled
omap: Fix omap_4430sdp_defconfig for make oldconfig
omap: Use CONFIG_SMP for test_for_ipi and test_for_ltirq
omap: Fix sev instruction usage for multi-omap
OMAP3: Fix a cpu type check problem
omap3: id: fix 3630 rev detection
Fix a comma that got accidentally deleted from sys_osf_statfs() leading to the
following warning:
arch/alpha/kernel/osf_sys.c: In function 'SYSC_osf_statfs':
arch/alpha/kernel/osf_sys.c:255: error: syntax error before 'buffer'
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that the driver for the Blackfin on-chip NFC no longer uses/respects
the page_size from the platform resources (figures out the needs on the
fly), drop it from the platform resources. This fixes some build errors
since the defines no longer exists.
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The common bfin_sport.h header now has unified definitions of these, so
stop polluting the global namespace.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Following occurs on boot message without this patch.
CPU1: processor failed to boot
Brought up 1 CPUs
SMP: Total of 1 processors activated...
This patch adds SYSRAM mapping for fixing Secondary CPU startup.
CPU1: Booted secondary processor
Brought up 2 CPUs
SMP: Total of 2 processors activated...
Signed-off-by: Changhwan Youn <chaos.youn@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This patch fixes on enable and ctrlbit of uclk1 and sclk_pwm.
Signed-off-by: Jongpill Lee <boyko.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This patch adds missed uart clocks for S5PV310/S5PC210.
Signed-off-by: Jongpill Lee <boyko.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This patch adds clk_sclk_apll so that fixes on clk_mout_apll.
Signed-off-by: Jongpill Lee <boyko.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This patch fixes on PLL setting for S5PV310/S5PC210.
Signed-off-by: Jongpill Lee <boyko.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This patch adds CMU block for S5PV310/S5PC210 clock.
(CMU: Clock Management Unit)
Of course, changed current clock addresses for it together.
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The S5PV310/S5PC210 has following three GPIO base addresses.
Part1 Base Address=0x11400000
Part2 Base Address=0x11000000
Part3 Base Address=0x03860000
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[kgene.kim@samsung.com: minor edit of title]
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Fix this warning:
arch/arm/mm/init.c: In function 'mem_init':
arch/arm/mm/init.c:644: warning: format '%08lx' expects type
'long unsigned int', but argument 12 has type 'unsigned int'
And removes the useless parens and white space.
Reported-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf, x86, Pentium4: Clear the P4_CCCR_FORCE_OVF flag
tracing/trace_stack: Fix stack trace on ppc64
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, tsc, sched: Recompute cyc2ns_offset's during resume from sleep states
sched: Fix rq->clock synchronization when migrating tasks
If on Pentium4 CPUs the FORCE_OVF flag is set then an NMI happens
on every event, which can generate a flood of NMIs. Clear it.
Reported-by: Vince Weaver <vweaver1@eecs.utk.edu>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc64: Get rid of indirect p1275 PROM call buffer.
sparc64: Fill a missing delay slot.
sparc64: Make lock backoff really a NOP on UP builds.
sparc64: simple microoptimizations for atomic functions
sparc64: Make rwsems 64-bit.
sparc64: Really fix atomic64_t interface types.
The tlb flushing code uses the mm_users field of the mm_struct to
decide if each page table entry needs to be flushed individually with
IPTE or if a global flush for the mm_struct is sufficient after all page
table updates have been done. The comment for mm_users says "How many
users with user space?" but the /proc code increases mm_users after it
found the process structure by pid without creating a new user process.
Which makes mm_users useless for the decision between the two tlb
flusing methods. The current code can be confused to not flush tlb
entries by a concurrent access to /proc files if e.g. a fork is in
progres. The solution for this problem is to make the tlb flushing
logic independent from the mm_users field.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
powerpc: Fix config dependency problem with MPIC_U3_HT_IRQS
via-pmu: Add compat_pmu_ioctl
powerpc: Wire up fanotify_init, fanotify_mark, prlimit64 syscalls
powerpc/pci: Fix checking for child bridges in PCI code.
powerpc: Fix typo in uImage target
powerpc: Initialise paca->kstack before early_setup_secondary
powerpc: Fix bogus it_blocksize in VIO iommu code
powerpc: Inline ppc64_runlatch_off
powerpc: Correct smt_enabled=X boot option for > 2 threads per core
powerpc: Silence xics_migrate_irqs_away() during cpu offline
powerpc: Silence __cpu_up() under normal operation
powerpc: Re-enable preemption before cpu_die()
powerpc/pci: Drop unnecessary null test
powerpc/powermac: Drop unnecessary null test
powerpc/powermac: Drop unnecessary of_node_put
powerpc/kdump: Stop all other CPUs before running crash handlers
powerpc/mm: Fix vsid_scrample typo
powerpc: Use is_32bit_task() helper to test 32 bit binary
powerpc: Export memstart_addr and kernstart_addr on ppc64
powerpc: Make rwsem use "long" type
...
fix this build error:
arch/s390/kernel/process.c:272: error: conflicting types for 'sys_execve'
arch/s390/kernel/entry.h:45: error: previous declaration of 'sys_execve' was here
make[1]: *** [arch/s390/kernel/process.o] Error 1
make: *** [arch/s390/kernel] Error 2
introduced by d7627467b7
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (29 commits)
ARM: imx: fix build failure concerning otg/ulpi
USB: ftdi_sio: add product ID for Lenz LI-USB
USB: adutux: fix misuse of return value of copy_to_user()
USB: iowarrior: fix misuse of return value of copy_to_user()
USB: xHCI: update ring dequeue pointer when process missed tds
USB: xhci: Remove buggy assignment in next_trb()
USB: ftdi_sio: Add ID for Ionics PlugComputer
USB: serial: io_ti.c: don't return 0 if writing the download record failed
USB: otg: twl4030: fix wrong assumption of starting state
USB: gadget: Return -ENOMEM on memory allocation failure
USB: gadget: fix composite kernel-doc warnings
USB: ssu100: set tty_flags in ssu100_process_packet
USB: ssu100: add disconnect function for ssu100
USB: serial: export symbol usb_serial_generic_disconnect
USB: ssu100: rework logic for TIOCMIWAIT
USB: ssu100: add register parameter to ssu100_setregister
USB: ssu100: remove duplicate #defines in ssu100
USB: ssu100: refine process_packet in ssu100
USB: ssu100: add locking for port private data in ssu100
USB: r8a66597-udc: return -ENOMEM if kzalloc() fails
...
This is based upon a report by Meelis Roos showing that it's possible
that we'll try to fetch a property that is 32K in size with some
devices. With the current fixed 3K buffer we use for moving data in
and out of the firmware during PROM calls, that simply won't work.
In fact, it will scramble random kernel data during bootup.
The reasoning behind the temporary buffer is entirely historical. It
used to be the case that we had problems referencing dynamic kernel
memory (including the stack) early in the boot process before we
explicitly told the firwmare to switch us over to the kernel trap
table.
So what we did was always give the firmware buffers that were locked
into the main kernel image.
But we no longer have problems like that, so get rid of all of this
indirect bounce buffering.
Besides fixing Meelis's bug, this also makes the kernel data about 3K
smaller.
It was also discovered during these conversions that the
implementation of prom_retain() was completely wrong, so that was
fixed here as well. Currently that interface is not in use.
Reported-by: Meelis Roos <mroos@linux.ee>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
MPIC_U3_HT_IRQS is selected both by PPC_PMAC64 and PPC_MAPLE, but depends
on PPC_MAPLE, so a PPC_PMAC64-only config gets this warning:
warning: (PPC_PMAC64 && PPC_PMAC && POWER4 || PPC_MAPLE && PPC64 && PPC_BOOK3S) selects MPIC_U3_HT_IRQS which has unmet direct dependencies (PPC_MAPLE)
Fix that by removing the dependency on PPC_MAPLE.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pci_device_to_OF_node() can return null, and list_for_each_entry will
never enter the loop when dev is NULL, so it looks like this test is
a typo.
Reported-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>