Mathias Krause [Tue, 5 Feb 2013 17:19:14 +0000 (18:19 +0100)]
crypto: user - fix empty string test in report API
The current test for empty strings fails because it is testing the
address of a field, not a pointer. So the test will always be true.
Test the first character in the string to not be null instead.
Mathias Krause [Tue, 5 Feb 2013 17:19:13 +0000 (18:19 +0100)]
crypto: user - fix info leaks in report API
Three errors resulting in kernel memory disclosure:
1/ The structures used for the netlink based crypto algorithm report API
are located on the stack. As snprintf() does not fill the remainder of
the buffer with null bytes, those stack bytes will be disclosed to users
of the API. Switch to strncpy() to fix this.
2/ crypto_report_one() does not initialize all field of struct
crypto_user_alg. Fix this to fix the heap info leak.
3/ For the module name we should copy only as many bytes as
module_name() returns -- not as much as the destination buffer could
hold. But the current code does not and therefore copies random data
from behind the end of the module name, as the module name is always
shorter than CRYPTO_MAX_ALG_NAME.
Also switch to use strncpy() to copy the algorithm's name and
driver_name. They are strings, after all.
Romain KUNTZ [Mon, 18 Feb 2013 02:36:24 +0000 (02:36 +0000)]
xfrm: release neighbor upon dst destruction
Neighbor is cloned in xfrm6_fill_dst but seems to never be released.
Neighbor entry should be released when XFRM6 dst entry is destroyed
in xfrm6_dst_destroy, otherwise references may be kept forever on
the device pointed by the neighbor entry.
I may not have understood all the subtleties of XFRM & dst so I would
be happy to receive comments on this patch.
Signed-off-by: Romain Kuntz <r.kuntz@ipflavors.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Mon, 18 Feb 2013 17:58:02 +0000 (09:58 -0800)]
mm: fix pageblock bitmap allocation
Commit c060f943d092 ("mm: use aligned zone start for pfn_to_bitidx
calculation") fixed out calculation of the index into the pageblock
bitmap when a !SPARSEMEM zome was not aligned to pageblock_nr_pages.
However, the _allocation_ of that bitmap had never taken this alignment
requirement into accout, so depending on the exact size and alignment of
the zone, the use of that index could then access past the allocation,
resulting in some very subtle memory corruption.
This was reported (and bisected) by Ingo Molnar: one of his random
config builds would hang with certain very specific kernel command line
options.
In the meantime, commit c060f943d092 has been marked for stable, so this
fix needs to be back-ported to the stable kernels that backported the
commit to use the right alignment.
Ying Xue [Fri, 15 Feb 2013 22:28:25 +0000 (22:28 +0000)]
net: fix a compile error when SOCK_REFCNT_DEBUG is enabled
When SOCK_REFCNT_DEBUG is enabled, below build error is met:
kernel/sysctl_binary.o: In function `sk_refcnt_debug_release':
include/net/sock.h:1025: multiple definition of `sk_refcnt_debug_release'
kernel/sysctl.o:include/net/sock.h:1025: first defined here
kernel/audit.o: In function `sk_refcnt_debug_release':
include/net/sock.h:1025: multiple definition of `sk_refcnt_debug_release'
kernel/sysctl.o:include/net/sock.h:1025: first defined here
make[1]: *** [kernel/built-in.o] Error 1
make: *** [kernel] Error 2
So we decide to make sk_refcnt_debug_release static to eliminate
the error.
Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sun, 17 Feb 2013 14:40:33 +0000 (14:40 +0000)]
ARM: add SCHED_HRTICK config option
As we don't include kernel/Kconfig.hz as this defines HZ values
unsuitable for ARM platforms, add the SCHED_HRTICK to properly configure
the scheduler for hrtimer operation.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ben Dooks [Mon, 11 Feb 2013 11:25:05 +0000 (12:25 +0100)]
ARM: 7650/1: mm: replace direct access to mm->context.id with new macro
The mmid macro is meant to be used to get the mm->context.id data
from the mm structure, but it seems to have been missed in a cuple
of files.
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ben Dooks [Mon, 11 Feb 2013 11:25:06 +0000 (12:25 +0100)]
ARM: 7649/1: mm: mm->context.id fix for big-endian
Since the new ASID code in b5466f8728527a05a493cc4abe9e6f034a1bbaab
("ARM: mm: remove IPI broadcasting on ASID rollover") was changed to
use 64bit operations it has broken the BE operation due to an issue
with the MM code accessing sub-fields of mm->context.id.
When running in BE mode we see the values in mm->context.id are stored
with the highest value first, so the LDR in the arch/arm/mm/proc-macros.S
reads the wrong part of this field. To resolve this, change the LDR in
the mmid macro to load from +4.
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Thierry Reding [Mon, 11 Feb 2013 07:46:10 +0000 (08:46 +0100)]
ARM: 7648/1: pci: Allow passing per-controller private data
In order to allow drivers to specify private data for each controller,
this commit adds a private_data field to the struct hw_pci. This field
is an array of nr_controllers pointers that will be used to initialize
the private_data field of the corresponding controller's pci_sys_data
structure.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Joonsoo Kim [Sat, 9 Feb 2013 05:28:06 +0000 (06:28 +0100)]
ARM: 7646/1: mm: use static_vm for managing static mapped areas
A static mapped area is ARM-specific, so it is better not to use
generic vmalloc data structure, that is, vmlist and vmlist_lock
for managing static mapped area. And it causes some needless overhead and
reducing this overhead is better idea.
Now, we have newly introduced static_vm infrastructure.
With it, we don't need to iterate all mapped areas. Instead, we just
iterate static mapped areas. It helps to reduce an overhead of finding
matched area. And architecture dependency on vmalloc layer is removed,
so it will help to maintainability for vmalloc layer.
Reviewed-by: Nicolas Pitre <nico@linaro.org> Acked-by: Rob Herring <rob.herring@calxeda.com> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Joonsoo Kim [Sat, 9 Feb 2013 05:28:05 +0000 (06:28 +0100)]
ARM: 7645/1: ioremap: introduce an infrastructure for static mapped area
In current implementation, we used ARM-specific flag, that is,
VM_ARM_STATIC_MAPPING, for distinguishing ARM specific static mapped area.
The purpose of static mapped area is to re-use static mapped area when
entire physical address range of the ioremap request can be covered
by this area.
This implementation causes needless overhead for some cases.
For example, assume that there is only one static mapped area and
vmlist has 300 areas. Every time we call ioremap, we check 300 areas for
deciding whether it is matched or not. Moreover, even if there is
no static mapped area and vmlist has 300 areas, every time we call
ioremap, we check 300 areas in now.
If we construct a extra list for static mapped area, we can eliminate
above mentioned overhead.
With a extra list, if there is one static mapped area,
we just check only one area and proceed next operation quickly.
In fact, it is not a critical problem, because ioremap is not frequently
used. But reducing overhead is better idea.
Another reason for doing this work is for removing architecture dependency
on vmalloc layer. I think that vmlist and vmlist_lock is internal data
structure for vmalloc layer. Some codes for debugging and stat inevitably
use vmlist and vmlist_lock. But it is preferable that they are used
as least as possible in outside of vmalloc.c
Now, I introduce an ARM-specific infrastructure for static mapped area. In
the following patch, we will use this and resolve above mentioned problem.
Reviewed-by: Nicolas Pitre <nico@linaro.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Erik Hugne [Thu, 14 Feb 2013 14:43:33 +0000 (14:43 +0000)]
tipc: fix missing spinlock init in broadcast code
After commit 3c294cb3 "tipc: remove the bearer congestion mechanism",
we try to grab the broadcast bearer lock when sending multicast
messages over the broadcast link. This will cause an oops because
the lock is never initialized. This is an old bug, but the lock
was never actually used before commit 3c294cb3, so that why it was
not visible until now. The oops will look something like:
The above can be triggered by running the multicast demo program.
Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Fri, 15 Feb 2013 20:12:55 +0000 (12:12 -0800)]
Merge tag 'stable/for-linus-3.8-rc7-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull xen fixes from Konrad Rzeszutek Wilk:
"Two fixes:
- A simple bug-fix for redundant NULL check.
- CVE-2013-0228/XSA-42: x86/xen: don't assume %ds is usable in
xen_iret for 32-bit PVOPS
and two reverts:
- Revert the PVonHVM kexec. The patch introduces a regression with
older hypervisor stacks, such as Xen 4.1."
* tag 'stable/for-linus-3.8-rc7-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
Revert "xen PVonHVM: use E820_Reserved area for shared_info"
Revert "xen/PVonHVM: fix compile warning in init_hvm_pv_info"
xen: remove redundant NULL check before unregister_and_remove_pcpu().
x86/xen: don't assume %ds is usable in xen_iret for 32-bit PVOPS.
Revert "[media] dvb_frontend: return -ENOTTY for unimplement IOCTL"
As reported by Klaus Schmidinger:
"In VDR I use an ioctl() call with FE_READ_UNCORRECTED_BLOCKS on a
device (using stb0899). After this call I check 'errno' for
EOPNOTSUPP to determine whether this device supports this call. This
used to work just fine, until a few months ago I noticed that my
devices using stb0899 didn't display their signal quality in VDR's OSD
any more. After further investigation I found that
ioctl(FE_READ_UNCORRECTED_BLOCKS) no longer returns EOPNOTSUPP, but
rather ENOTTY. And since I stop getting the signal quality in case
any unknown errno value appears, this broke my signal quality query
function."
Linus Torvalds [Fri, 15 Feb 2013 20:04:57 +0000 (12:04 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull one more x86 fix from Peter Anvin:
"Sigh. One more patch in the "please don't brick my Samsung" series"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Clear EFI_RUNTIME_SERVICES rather than EFI_BOOT by "noefi" boot parameter
Linus Torvalds [Fri, 15 Feb 2013 20:04:08 +0000 (12:04 -0800)]
Merge tag '3.8-pci-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fix from Bjorn Helgaas:
"This is another fix for v3.8. It fixes an oops that happens when a
Thunderbolt adapter is unplugged (remove device, poll for PME events
on no-longer-existing device, oops)."
* tag '3.8-pci-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI/PM: Clean up PME state when removing a device
Linus Torvalds [Fri, 15 Feb 2013 20:03:09 +0000 (12:03 -0800)]
Merge tag 'omapdss-for-3.8-rc8' of git://gitorious.org/linux-omap-dss2/linux
Pull omapdss fixes from Tomi Valkeinen:
"It'd be great if these two late fixes would still make it into 3.8.
The other one fixes ARM kernel compilation when using 'allyesconfig',
and the other makes DPI displays function again on OMAP3630 boards:
- Fix ARM compilation with "allyesconfig" (omapdrm: fix the
dependency to omapdss)
- fix DPI displays on OMAP3630 (OMAPDSS: add FEAT_DPI_USES_VDDS_DSI
to omap3630_dss_feat_list)"
* tag 'omapdss-for-3.8-rc8' of git://gitorious.org/linux-omap-dss2/linux:
omapdrm: fix the dependency to omapdss
OMAPDSS: add FEAT_DPI_USES_VDDS_DSI to omap3630_dss_feat_list
Linus Torvalds [Fri, 15 Feb 2013 19:59:27 +0000 (11:59 -0800)]
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c maintainer info update from Wolfram Sang:
"Since my old email and repos are not working anymore, and this already
caused some confusion, I think a MAINTAINERS update for 3.8 is
helpful. So, people trying I2C with the new kernel can properly reach
me and find my repos."
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
MAINTAINERS: change my email and repos
Vineet Gupta [Mon, 11 Feb 2013 09:10:55 +0000 (14:40 +0530)]
ARC: Fix pt_orig_r8 access
Syscall restarting fixes made pt_regs->orig_r8 a short word, which was
not reflected in the assembler code - thus could potentially break gdb
debugging.
Vineet Gupta [Wed, 6 Feb 2013 09:39:13 +0000 (15:09 +0530)]
ARC: 64bit RTSC timestamp hardware issue
The 64bit RTSC is not reliable, causing spurious "jumps" in higher word,
making Linux timekeeping go bonkers. So as of now just use the lower
32bit timestamp.
A cleaner approach would have been removing RTSC support altogether as the
32bit RTSC is equivalent to old TIMER1 based solution, but some customers
can use the 32bit RTSC in SMP syn fashion (vs. TIMER1 which being incore
can't be done easily).
A fallout of this is sched_clock()'s hardware assisted version needs to
go away since it can't use 32bit wrapping counter - instead we use the
generic "weak" jiffies based version.
Vineet Gupta [Mon, 28 Jan 2013 09:37:31 +0000 (15:07 +0530)]
ARC: Don't fiddle with non-existent caches
!CONFIG_ARC_HAS_(I|D)CACHE makes Linux disable caches (assuming they
exist in hardware) - mostly for debugging issues with new peripherals.
However, independent of CONFIG_ARC_HAS_(I|D)CACHE, Linux also needs to
handle, non-existant caches, using the information in Cache BCRs (Build
Configuration Reg)
All the current platforms can work with 0x8000_0000 based dma_addr_t
since the Bus Bridges typically ignore the top bit (the only excpetion
was Angel4 PCI-AHB bridge which we no longer care for).
That way we don't need plat-specific cpu-addr to bus-addr conversion.
Hooks still provided - just in case a platform has an obscure device
which say needs 0 based bus address.
That way <asm/dma_mapping.h> no longer needs to unconditinally include
<plat/dma_addr.h>
Also verfied that on Angel4 board, other peripherals (IDE-disk / EMAC)
work fine with 0x8000_0000 based dma addresses.
The orig platform code orgnaization was singleton design pattern - only
one platform (and board thereof) would build at a time.
Thus any platform/board specific code (e.g. irq init, early init ...)
expected by ARC common code was exported as well defined set of APIs,
with only ONE instance building ever.
Now with multiple-platform build requirement, that design of code no
longer holds - multiple board specific calls need to build at the same
time - so ARC common code can't use the API approach, it needs a
callback based design where each board registers it's specific set of
functions, and at runtime, depending on board detection, the callbacks
are used from the registry.
This commit adds all the infrastructure, where board specific callbacks
are specified as a "maThine description".
All the hooks are placed in right spots, no board callbacks registered
yet (with MACHINE_STARt/END constructs) so the hooks will not run.
Next commit will actually convert the platform to this infrastructure.
This mini patchseries addresses the lack of multi-platform-image support
in ARC port.
Older build system only supported one platform(soc) to build at a time
and further only one board of that platform could be built. There was no
technical reason for that - we just didn't have the need.
So the first step towards multi-platform (and multi-board) builds it to
allow build system to do that.
So as applicable, <choice .. endchoice> => <menu .. endmenu>
Gilad Ben-Yossef [Tue, 22 Jan 2013 11:18:45 +0000 (16:48 +0530)]
ARC: Add support for ioremap_prot API
Implement ioremap_prot() to allow mapping IO memory with variable
protection
via TLB.
Implementing this allows the /dev/mem driver to use its generic access()
VMA callback, which in turn allows ptrace to examine data in memory
mapped regions mapped via /dev/mem, such as Arc DCCM.
The end result is that it is possible to examine values of variables
placed into DCCM in user space programs via GDB.
Vineet Gupta [Fri, 18 Jan 2013 09:42:25 +0000 (15:12 +0530)]
ARC: Support for single cycle Close Coupled Mem (CCM)
* Includes mapping of CCMs in address space
* Annotations to move arbitrary code/data into CCM
* Moving some of the critical code/data into CCM
* Runtime detection/reporting
Vineet Gupta [Wed, 23 Jan 2013 11:00:36 +0000 (16:30 +0530)]
ARC: Unaligned access emulation
ARC700 doesn't natively support unaligned access, but can be emulated
-Unaligned Access Exception
-Disassembly at the Fault address to find the exact insn (long/short)
Also per Arnd's comment, we runtime control it using 2 sysctl knobs:
* SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble
* SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt
Originally contributed by Tim Yao <tim.yao@amlogic.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Tim Yao <tim.yao@amlogic.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
Vineet Gupta [Fri, 18 Jan 2013 09:42:23 +0000 (15:12 +0530)]
ARC: SMP support
ARC common code to enable a SMP system + ISS provided SMP extensions.
ARC700 natively lacks SMP support, hence some of the core features are
are only enabled if SoCs have the necessary h/w pixie-dust. This
includes:
-Inter Processor Interrupts (IPI)
-Cache coherency
-load-locked/store-conditional
...
The low level exception handling would be completely broken in SMP
because we don't have hardware assisted stack switching. Thus a fair bit
of this code is repurposing the MMU_SCRATCH reg for event handler
prologues to keep them re-entrant.
Many thanks to Rajeshwar Ranga for his initial "major" contributions to
SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help
with resurrecting that in 3.2 kernel (2012).
Note that this platform code is again singleton design pattern - so
multiple SMP platforms won't build at the moment - this deficiency is
addressed in subsequent patches within this series.
Vineet Gupta [Fri, 18 Jan 2013 09:42:22 +0000 (15:12 +0530)]
ARC: [plat-arcfpga] defconfig
With this we get to a running kernel on ISS
---------------------------------->8-----------------------------------
Linux version 3.8.0-rc3+ (vineetg@vineetg-Latitude) (gcc version 4.4.7
(ARCompact elf32 toolchain (built 20121213)) ) #3 Thu Jan 17 14:22:05
IST 2013
Board "arc-angel4" from snps (Manufacturer)
Memory size set via devicetree 256M
[plat-arcfpga]: registering early dev resources
bootconsole [early_ARCuart0] enabled
pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768
pcpu-alloc: [0] 0
Built 1 zonelists in Zone order, mobility grouping on. Total pages:
32624
Kernel command line: console=ttyARC0,115200n8
PID hash table entries: 1024 (order: -1, 4096 bytes)
Dentry cache hash table entries: 32768 (order: 4, 131072 bytes)
Inode-cache hash table entries: 16384 (order: 3, 65536 bytes)
Memory Available: 248M / 256M (1312K code, 463K data, 4184K init, 1400K
reserv)
SLUB: Genslabs=12, HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
NR_IRQS:16
Console: colour dummy device 80x25
Calibrating delay loop... 39.73 BogoMIPS (lpj=198656)
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 1024
devtmpfs: initialized
[plat-arcfpga]: registering device resources
bio: create slab <bio-0> at 0
Switching to clocksource ARC RTSC
io scheduler noop registered (default)
arc-uart: ttyARC0 at MMIO 0xc0fc1000 (irq = 5) is a arc-uart
console [ttyARC0] enabled, bootconsole disabled
console [ttyARC0] enabled, bootconsole disabled
mousedev: PS/2 mouse device common for all mice
Warning: unable to open an initial console.
Freeing unused kernel memory: 4184k [80002000] to [80418000]
Mounting proc
Mounting sysfs
Mounting devpts
Setting hostname to ARCLinux
Starting System logger (syslogd)
Bringing up loopback device
ifconfig: socket: Function not implemented
route: socket: Function not implemented
Disk not detected !
Mounting tmpfs
mount: mounting tmpfs on /dev/shm failed: Invalid argument
/etc/init.d/rcS: line 76: can't create /proc/sys/kernel/msgmni:
nonexistent directory
Please press Enter to activate this console.
***********************************************************************
Welcome to ARCLinux
***********************************************************************
[ARCLinux]$
Vineet Gupta [Fri, 18 Jan 2013 09:42:21 +0000 (15:12 +0530)]
ARC: Last bits (stubs) to get to a running kernel with UART
This was part of port buildup strategy from Arnd to have a minimal kernel
at first and then add optional features (stacktracing, ptrace, smp,
kprobes, oprofile....)
Vineet Gupta [Tue, 22 Jan 2013 11:30:52 +0000 (17:00 +0530)]
ARC: [DeviceTree] Basic support
This is minimal infrastructure needed for devicetree work.
It uses an a sample "skeleton" devicetree - embedded in kernel image -
to print the board, manufacturer by parsing the top-level "compatible"
string.
As of now we don't need any additional "board" specific "machine_desc".
TODO: support interpreting the command line as boot-loader passed dtb
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: devicetree-discuss@lists.ozlabs.org Cc: Rob Herring <rob.herring@calxeda.com> Cc: James Hogan <james.hogan@imgtec.com> Reviewed-by: Rob Herring <rob.herring@calxeda.com> Reviewed-by: James Hogan <james.hogan@imgtec.com>
Vineet Gupta [Fri, 18 Jan 2013 09:42:20 +0000 (15:12 +0530)]
ARC: [plat-arcfpga] Static platform device for CONFIG_SERIAL_ARC
N.B. This is old style of hardcoding platform device specific info
in code and it's instantiation thererof using platform_add_devices().
Subsequent patches replace this with DeviceTree based runtime probe.
This patch has been retained just as an example of "don't-do-this" for
newer kernel ports.
Vineet Gupta [Fri, 18 Jan 2013 09:42:20 +0000 (15:12 +0530)]
ARC: Page Fault handling
This includes recent changes to make handler "retry" and/or "killable"
The killable (early exit) logic is loosely based on how SH implements it
return if SIGKILL + either of VM_FAULT_OOM or VM_FAULT_RETRY
which is different from Hexagon implementation which would NOT early
exit for
SIGKILL + VM_FAULT_OOM + !VM_FAULT_RETRY
credits: Non executable stack support from Simon Spooner
Vineet Gupta [Fri, 18 Jan 2013 09:42:19 +0000 (15:12 +0530)]
ARC: Cache Flush Management
* ARC700 has VIPT L1 Caches
* Caches don't snoop and are not coherent
* Given the PAGE_SIZE and Cache associativity, we don't support aliasing
D$ configurations (yet), but do allow aliasing I$ configs
Vineet Gupta [Fri, 18 Jan 2013 09:42:19 +0000 (15:12 +0530)]
ARC: [Review] Prevent incorrect syscall restarts
Per Al Viro's "signals for dummies" https://lkml.org/lkml/2012/12/6/366
there are 3 golden rules for (not) restarting syscalls:
" What we need to guarantee is
* restarts do not happen on signals caught in interrupts or exceptions
* restarts do not happen on signals caught in sigreturn()
* restart should happen only once, even if we get through do_signal()
many times."
ARC Port already handled #1, this patch fixes #2 and #3.
We use the additional state in pt_regs->orig_r8 to ckh if restarting
has already been done once.
Thanks to Al Viro for spotting this.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
Vineet Gupta [Mon, 11 Feb 2013 14:31:24 +0000 (20:01 +0530)]
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals
To avoid multiple syscall restarts (multiple signals) or no restart at
all (sigreturn), we need just an extra bit of state "literally 1 bit" in
struct pt_regs. orig_r8 is the best place to do this, however given the
way it is encoded currently, we can't add anything simplistically.
Current orig_r8:
* syscalls -> 1 to NR_SYSCALLS
* Exceptions -> NR_SYSCALLS + 1
* Break-point-> NR_SYSCALLS + 2
In new scheme it is a bit-field
* lower short word contains the exact event type (and a new bit to represent
restart semantics : if syscall was already / can't be restarted)
* upper short word optionally containing the syscall num - needed by
likes of tracehooks etc
This patch only changes how orig_r8 is organised and nothing should
change behaviourily.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>