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Individual CPUs may have special requirements to not enter
deep idle states. For example, a CPU running real time
applications would not want to enter deep idle states to
avoid latency impacts. At the same time other CPUs that
do not have such a requirement could allow deep idle
states to save power.
This was already implemented in the menu governor.
Implementing similar changes in the ladder governor which
gets selected when CONFIG_NO_HZ and CONFIG_NO_HZ_IDLE are not
set. Refer following commits for the menu governor changes.
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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The special value of 0 for device resume latency PM QoS means
"no restriction", but there are two problems with that.
First, device resume latency PM QoS requests with 0 as the
value are always put in front of requests with positive
values in the priority lists used internally by the PM QoS
framework, causing 0 to be chosen as an effective constraint
value. However, that 0 is then interpreted as "no restriction"
effectively overriding the other requests with specific
restrictions which is incorrect.
Second, the users of device resume latency PM QoS have no
way to specify that *any* resume latency at all should be
avoided, which is an artificial limitation in general.
To address these issues, modify device resume latency PM QoS to
use S32_MAX as the "no constraint" value and 0 as the "no
latency at all" one and rework its users (the cpuidle menu
governor, the genpd QoS governor and the runtime PM framework)
to follow these changes.
Also add a special "n/a" value to the corresponding user space I/F
to allow user space to indicate that it cannot accept any resume
latencies at all for the given device.
Fixes: 85dc0b8a4019 (PM / QoS: Make it possible to expose PM QoS latency constraints)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
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The genpd governor currently uses negative PM QoS values to indicate
the "no suspend" condition and 0 as "no restriction", but it doesn't
use them consistently. Moreover, it tries to refresh QoS values for
already suspended devices in a quite questionable way.
For the above reasons, rework it to be a bit more consistent.
First off, note that dev_pm_qos_read_value() in
dev_update_qos_constraint() and __default_power_down_ok() is
evaluated for devices in suspend. Moreover, that only happens if the
effective_constraint_ns value for them is negative (meaning "no
suspend"). It is not evaluated in any other cases, so effectively
the QoS values are only updated for devices in suspend that should
not have been suspended in the first place. In all of the other
cases, the QoS values taken into account are the effective ones from
the time before the device has been suspended, so generally devices
need to be resumed and suspended again for new QoS values to take
effect anyway. Thus evaluating dev_update_qos_constraint() in
those two places doesn't make sense at all, so drop it.
Second, initialize effective_constraint_ns to 0 ("no constraint")
rather than to (-1) ("no suspend"), which makes more sense in
general and in case effective_constraint_ns is never updated
(the device is in suspend all the time or it is never suspended)
it doesn't affect the device's parent and so on.
Finally, rework default_suspend_ok() to explicitly handle the
"no restriction" and "no suspend" special cases.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
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It's difficult for me to handle upstream mail that ends up in my work
account and this was done outside of work anyway so replace my work
address with my usual address for upstream stuff.
Signed-off-by: Mark Brown <broonie@kernel.org>
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Update list of available compiled-in fonts in lib/fonts/:
add 6x10 and drop RomanLarge (which was reverted 12 years ago).
Also sort the list alphabetically.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # v1
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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Building an allnoconfig kernel based on the ralink platform results in
the following warning:
warning: (SOC_RT305X) selects USB_ARCH_HAS_HCD which has unmet direct dependencies (USB_SUPPORT)
This is because SOC_RT305X unconditionally selects USB_ARCH_HAS_HCD
which depends on USB_SUPPORT.
However USB_ARCH_HAS_HCD has been effectively obsolete since commit
d9ea21a77927 ("usb: host: make USB_ARCH_HAS_?HCI obsolete") in 3.11.
USB_ARCH_HAS_HCD is now set by default whenever USB_SUPPORT is, so drop
the select to silence the warning.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Crispin <john@phrozen.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17618/
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The STR and SLDT instructions are not valid when running on virtual-8086
mode and generate an invalid operand exception. These two instructions are
protected by the Intel User-Mode Instruction Prevention (UMIP) security
feature. In protected mode, if UMIP is enabled, these instructions generate
a general protection fault if called from CPL > 0. Linux traps the general
protection fault and emulates the instructions sgdt, sidt and smsw; but not
str and sldt.
These tests are added to verify that the emulation code does not emulate
these two instructions but the expected invalid operand exception is
seen.
Tests fallback to exit with INT3 in case emulation does happen.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-13-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Certain user space programs that run on virtual-8086 mode may utilize
instructions protected by the User-Mode Instruction Prevention (UMIP)
security feature present in new Intel processors: SGDT, SIDT and SMSW. In
such a case, a general protection fault is issued if UMIP is enabled. When
such a fault happens, the kernel traps it and emulates the results of
these instructions with dummy values. The purpose of this new
test is to verify whether the impacted instructions can be executed
without causing such #GP. If no #GP exceptions occur, we expect to exit
virtual-8086 mode from INT3.
The instructions protected by UMIP are executed in representative use
cases:
a) displacement-only memory addressing
b) register-indirect memory addressing
c) results stored directly in operands
Unfortunately, it is not possible to check the results against a set of
expected values because no emulation will occur in systems that do not
have the UMIP feature. Instead, results are printed for verification. A
simple verification is done to ensure that results of all tests are
identical.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-12-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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If the User-Mode Instruction Prevention CPU feature is available and
enabled, a general protection fault will be issued if the instructions
sgdt, sldt, sidt, str or smsw are executed from user-mode context
(CPL > 0). If the fault was caused by any of the instructions protected
by UMIP, fixup_umip_exception() will emulate dummy results for these
instructions as follows: in virtual-8086 and protected modes, sgdt, sidt
and smsw are emulated; str and sldt are not emulated. No emulation is done
for user-space long mode processes.
If emulation is successful, the emulated result is passed to the user space
program and no SIGSEGV signal is emitted.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-11-git-send-email-ricardo.neri-calderon@linux.intel.com
[ Added curly braces. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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User-Mode Instruction Prevention (UMIP) is enabled by setting/clearing a
bit in %cr4.
It makes sense to enable UMIP at some point while booting, before user
spaces come up. Like SMAP and SMEP, is not critical to have it enabled
very early during boot. This is because UMIP is relevant only when there is
a user space to be protected from. Given these similarities, UMIP can be
enabled along with SMAP and SMEP.
At the moment, UMIP is disabled by default at build time. It can be enabled
at build time by selecting CONFIG_X86_INTEL_UMIP. If enabled at build time,
it can be disabled at run time by adding clearcpuid=514 to the kernel
parameters.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-10-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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fixup_umip_exception() will be called from do_general_protection(). If the
former returns false, the latter will issue a SIGSEGV with SEND_SIG_PRIV.
However, when emulation is successful but the emulated result cannot be
copied to user space memory, it is more accurate to issue a SIGSEGV with
SEGV_MAPERR with the offending address. A new function, inspired in
force_sig_info_fault(), is introduced to model the page fault.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-9-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The feature User-Mode Instruction Prevention present in recent Intel
processor prevents a group of instructions (sgdt, sidt, sldt, smsw, and
str) from being executed with CPL > 0. Otherwise, a general protection
fault is issued.
Rather than relaying to the user space the general protection fault caused
by the UMIP-protected instructions (in the form of a SIGSEGV signal), it
can be trapped and the instruction emulated to provide a dummy result.
This allows to both conserve the current kernel behavior and not reveal the
system resources that UMIP intends to protect (i.e., the locations of the
global descriptor and interrupt descriptor tables, the segment selectors of
the local descriptor table, the value of the task state register and the
contents of the CR0 register).
This emulation is needed because certain applications (e.g., WineHQ and
DOSEMU2) rely on this subset of instructions to function. Given that sldt
and str are not commonly used in programs that run on WineHQ or DOSEMU2,
they are not emulated. Also, emulation is provided only for 32-bit
processes; 64-bit processes that attempt to use the instructions that UMIP
protects will receive the SIGSEGV signal issued as a consequence of the
general protection fault.
The instructions protected by UMIP can be split in two groups. Those which
return a kernel memory address (sgdt and sidt) and those which return a
value (smsw, sldt and str; the last two not emulated).
For the instructions that return a kernel memory address, applications such
as WineHQ rely on the result being located in the kernel memory space, not
the actual location of the table. The result is emulated as a hard-coded
value that lies close to the top of the kernel memory. The limit for the
GDT and the IDT are set to zero.
The instruction smsw is emulated to return the value that the register CR0
has at boot time as set in the head_32.
Care is taken to appropriately emulate the results when segmentation is
used. That is, rather than relying on USER_DS and USER_CS, the function
insn_get_addr_ref() inspects the segment descriptor pointed by the
registers in pt_regs. This ensures that we correctly obtain the segment
base address and the address and operand sizes even if the user space
application uses a local descriptor table.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-8-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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User-Mode Instruction Prevention is a security feature present in new
Intel processors that, when set, prevents the execution of a subset of
instructions if such instructions are executed in user mode (CPL > 0).
Attempting to execute such instructions causes a general protection
exception.
The subset of instructions comprises:
* SGDT - Store Global Descriptor Table
* SIDT - Store Interrupt Descriptor Table
* SLDT - Store Local Descriptor Table
* SMSW - Store Machine Status Word
* STR - Store Task Register
This feature is also added to the list of disabled-features to allow
a cleaner handling of build-time configuration.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-7-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Tasks running in virtual-8086 mode, in protected mode with code segment
descriptors that specify 16-bit default address sizes via the D bit, or via
an address override prefix will use 16-bit addressing form encodings as
described in the Intel 64 and IA-32 Architecture Software Developer's
Manual Volume 2A Section 2.1.5, Table 2-1.
16-bit addressing encodings differ in several ways from the 32-bit/64-bit
addressing form encodings: ModRM.rm points to different registers and, in
some cases, effective addresses are indicated by the addition of the value
of two registers. Also, there is no support for SIB bytes. Thus, a
separate function is needed to parse this form of addressing.
Three functions are introduced. get_reg_offset_16() obtains the
offset from the base of pt_regs of the registers indicated by the ModRM
byte of the address encoding. get_eff_addr_modrm_16() computes the
effective address from the value of the register operands.
get_addr_ref_16() computes the linear address using the obtained effective
address and the base address of the segment.
Segment limits are enforced when running in protected mode.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-6-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
It is possible to utilize 32-bit address encodings in virtual-8086 mode via
an address override instruction prefix. However, the range of the
effective address is still limited to [0x-0xffff]. In such a case, return
error.
Also, linear addresses in virtual-8086 mode are limited to 20 bits. Enforce
such limit by truncating the most significant bytes of the computed linear
address.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-5-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
The function insn_get_addr_ref() is capable of handling only 64-bit
addresses. A previous commit introduced a function to handle 32-bit
addresses. Invoke these two functions from a third wrapper function that
calls the appropriate routine based on the address size specified in the
instruction structure (obtained by looking at the code segment default
address size and the address override prefix, if present).
While doing this, rename the original function insn_get_addr_ref() with
the more appropriate name get_addr_ref_64(), ensure it is only used
for 64-bit addresses.
Also, since 64-bit addresses are not possible in 32-bit builds, provide
a dummy function such case.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-4-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
32-bit and 64-bit address encodings are identical. Thus, the same logic
could be used to resolve the effective address. However, there are two key
differences: address size and enforcement of segment limits.
If running a 32-bit process on a 64-bit kernel, it is best to perform
the address calculation using 32-bit data types. In this manner hardware
is used for the arithmetic, including handling of signs and overflows.
32-bit addresses are generally used in protected mode; segment limits are
enforced in this mode. This implementation obtains the limit of the
segment associated with the instruction operands and prefixes. If the
computed address is outside the segment limits, an error is returned. It
is also possible to use 32-bit address in long mode and virtual-8086 mode
by using an address override prefix. In such cases, segment limits are not
enforced.
Support to use 32-bit arithmetic is added to the utility functions that
compute effective addresses. However, the end result is stored in a
variable of type long (which has a width of 8 bytes in 64-bit builds).
Hence, once a 32-bit effective address is computed, the 4 most significant
bytes are masked out to avoid sign extension.
The newly added function get_addr_ref_32() is almost identical to the
existing function insn_get_addr_ref() (used for 64-bit addresses). The only
difference is that it verifies that the effective address is within the
limits of the segment.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-3-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Computing a linear address involves several steps. The first step is to
compute the effective address. This requires determining the addressing
mode in use and perform arithmetic operations on the operands. Plus, each
addressing mode has special cases that must be handled.
Once the effective address is known, the base address of the applicable
segment is added to obtain the linear address.
Clearly, this is too much work for a single function. Instead, handle each
addressing mode in a separate utility function. This improves readability
and gives us the opportunity to handler errors better.
At the moment, arithmetic to compute the effective address uses 64-byte
variables. Thus, limit support to 64-bit addresses.
While reworking the function insn_get_addr_ref(), the variable addr_offset
is renamed as regoff to reflect its actual use (i.e., offset, from the
base of pt_regs, of the register used as operand).
Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-2-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Lockdep now has an integrated IRQs disabled/enabled sanity check. Just
use it instead of the ad-hoc RCU version.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-15-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-14-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-13-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-12-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-11-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-10-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-9-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
It also makes no more sense to fix the IRQ flags when a bug is detected
as the assertion is now pure config-dependent debugging. And to quote
Peter Zijlstra:
The whole if !disabled, disable logic is uber paranoid programming,
but I don't think we've ever seen that WARN trigger, and if it does
(and then burns the kernel) we at least know what happend.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-8-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-7-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-6-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1509980490-4285-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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lockdep_assert_irqs_enabled()/disabled()
Checking whether IRQs are enabled or disabled is a very common sanity
check, however not free of overhead especially on fastpath where such
assertion is very common.
Lockdep is a good host for such concurrency correctness check and it
even already tracks down IRQs disablement state. Just reuse its
machinery. This will allow us to get rid of the flags pop and check
overhead from fast path when kernel is built for production.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-2-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The UMIP series is based on top of changes already queued up in the x86/mpx branch,
so merge it.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Fengguang reported a KASAN warning:
Kprobe smoke test: started
==================================================================
BUG: KASAN: stack-out-of-bounds in deref_stack_reg+0xb5/0x11a
Read of size 8 at addr ffff8800001c7cd8 by task swapper/1
CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.0-rc8 #26
Call Trace:
<#DB>
...
save_trace+0xd9/0x1d3
mark_lock+0x5f7/0xdc3
__lock_acquire+0x6b4/0x38ef
lock_acquire+0x1a1/0x2aa
_raw_spin_lock_irqsave+0x46/0x55
kretprobe_table_lock+0x1a/0x42
pre_handler_kretprobe+0x3f5/0x521
kprobe_int3_handler+0x19c/0x25f
do_int3+0x61/0x142
int3+0x30/0x60
[...]
The ORC unwinder got confused by some kprobes changes, which isn't
surprising since the runtime code no longer matches vmlinux and the
stack was modified for kretprobes.
Until we have a way for generated code to register changes with the
unwinder, these types of warnings are inevitable. So just disable KASAN
checks for stack accesses in the ORC unwinder.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171108021934.zbl6unh5hpugybc5@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Currently, all the lock waiters entering the slowpath will do one
lock stealing attempt to acquire the lock. That helps performance,
especially in VMs with over-committed vCPUs. However, the current
pvqspinlocks still don't perform as good as unfair locks in many cases.
On the other hands, unfair locks do have the problem of lock starvation
that pvqspinlocks don't have.
This patch combines the best attributes of an unfair lock and a
pvqspinlock into a hybrid lock with 2 modes - queued mode & unfair
mode. A lock waiter goes into the unfair mode when there are waiters
in the wait queue but the pending bit isn't set. Otherwise, it will
go into the queued mode waiting in the queue for its turn.
On a 2-socket 36-core E5-2699 v3 system (HT off), a kernel build
(make -j<n>) was done in a VM with unpinned vCPUs 3 times with the
best time selected and <n> is the number of vCPUs available. The build
times of the original pvqspinlock, hybrid pvqspinlock and unfair lock
with various number of vCPUs are as follows:
vCPUs pvqlock hybrid pvqlock unfair lock
----- ------- -------------- -----------
30 342.1s 329.1s 329.1s
36 314.1s 305.3s 307.3s
45 345.0s 302.1s 306.6s
54 365.4s 308.6s 307.8s
72 358.9s 293.6s 303.9s
108 343.0s 285.9s 304.2s
The hybrid pvqspinlock performs better or comparable to the unfair
lock.
By turning on QUEUED_LOCK_STAT, the table below showed the number
of lock acquisitions in unfair mode and queue mode after a kernel
build with various number of vCPUs.
vCPUs queued mode unfair mode
----- ----------- -----------
30 9,130,518 294,954
36 10,856,614 386,809
45 8,467,264 11,475,373
54 6,409,987 19,670,855
72 4,782,063 25,712,180
It can be seen that as the VM became more and more over-committed,
the ratio of locks acquired in unfair mode increases. This is all
done automatically to get the best overall performance as possible.
Using a kernel locking microbenchmark with number of locking
threads equals to the number of vCPUs available on the same machine,
the minimum, average and maximum (min/avg/max) numbers of locking
operations done per thread in a 5-second testing interval are shown
below:
vCPUs hybrid pvqlock unfair lock
----- -------------- -----------
36 822,135/881,063/950,363 75,570/313,496/ 690,465
54 542,435/581,664/625,937 35,460/204,280/ 457,172
72 397,500/428,177/499,299 17,933/150,679/ 708,001
108 257,898/288,150/340,871 3,085/181,176/1,257,109
It can be seen that the hybrid pvqspinlocks are more fair and
performant than the unfair locks in this test.
The table below shows the kernel build times on a smaller 2-socket
16-core 32-thread E5-2620 v4 system.
vCPUs pvqlock hybrid pvqlock unfair lock
----- ------- -------------- -----------
16 436.8s 433.4s 435.6s
36 366.2s 364.8s 364.5s
48 423.6s 376.3s 370.2s
64 433.1s 376.6s 376.8s
Again, the performance of the hybrid pvqspinlock was comparable to
that of the unfair lock.
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1510089486-3466-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Remove the support to create a z/VM named saved segment (NSS). This
feature is not supported since quite a while in favour of jump labels,
function tracing and (now) CPU alternatives. All of these features
require to write to the kernel text section which is not possible if
the kernel is contained within an NSS.
Given that memory savings are minimal if kernel images are shared and
in addition updates of shared images are painful, the NSS feature can
be removed.
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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The reworked version of the random device driver now calls
the arch_get_random_* functions on a very high frequency.
It does about 100.000 calls to arch_get_random_long for
providing 10 MB via /dev/urandom. Each invocation was
fetching entropy from the hardware random generator which
has a rate limit of about 4 MB/s. As the trng invocation
waits until enough entropy is gathered, the random device
driver is slowed down dramatically.
The s390 true random generator is not designed for such
a high rate. The TRNG is more designed to be used together
with the arch_get_random_seed_* functions. This is similar
to the way how powerpc has implemented their arch random
functionality.
This patch removes the invocations of the s390 TRNG for
arch_get_random_long() and arch_get_random_int() but leaving
the invocations for arch_get_random_seed_long() and
arch_get_random_seed_int(). So the s390 arch random
implementation now contributes high quality entropy to
the kernel random device for reseeding.
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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As of today QEMU does not provide the AIS facility to its guest. This
prevents Linux guests from using PCI devices as the ais facility is
checked during init. As this is just a performance optimization, we can
move the ais check into the code where we need it (calling the SIC
instruction). This is used at initialization and on interrupt. Both
places do not require any serialization, so we can simply skip the
instruction.
Since we will now get all interrupts, we can also avoid the 2nd scan.
As we can have multiple interrupts in parallel we might trigger spurious
irqs more often for the non-AIS case but the core code can handle that.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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v16->17
- Fixed disputed check code: keep them in nsh_push and nsh_pop
but also add them in __ovs_nla_copy_actions
v15->v16
- Add csum recalculation for nsh_push, nsh_pop and set_nsh
pointed out by Pravin
- Move nsh key into the union with ipv4 and ipv6 and add
check for nsh key in match_validate pointed out by Pravin
- Add nsh check in validate_set and __ovs_nla_copy_actions
v14->v15
- Check size in nsh_hdr_from_nlattr
- Fixed four small issues pointed out By Jiri and Eric
v13->v14
- Rename skb_push_nsh to nsh_push per Dave's comment
- Rename skb_pop_nsh to nsh_pop per Dave's comment
v12->v13
- Fix NSH header length check in set_nsh
v11->v12
- Fix missing changes old comments pointed out
- Fix new comments for v11
v10->v11
- Fix the left three disputable comments for v9
but not fixed in v10.
v9->v10
- Change struct ovs_key_nsh to
struct ovs_nsh_key_base base;
__be32 context[NSH_MD1_CONTEXT_SIZE];
- Fix new comments for v9
v8->v9
- Fix build error reported by daily intel build
because nsh module isn't selected by openvswitch
v7->v8
- Rework nested value and mask for OVS_KEY_ATTR_NSH
- Change pop_nsh to adapt to nsh kernel module
- Fix many issues per comments from Jiri Benc
v6->v7
- Remove NSH GSO patches in v6 because Jiri Benc
reworked it as another patch series and they have
been merged.
- Change it to adapt to nsh kernel module added by NSH
GSO patch series
v5->v6
- Fix the rest comments for v4.
- Add NSH GSO support for VxLAN-gpe + NSH and
Eth + NSH.
v4->v5
- Fix many comments by Jiri Benc and Eric Garver
for v4.
v3->v4
- Add new NSH match field ttl
- Update NSH header to the latest format
which will be final format and won't change
per its author's confirmation.
- Fix comments for v3.
v2->v3
- Change OVS_KEY_ATTR_NSH to nested key to handle
length-fixed attributes and length-variable
attriubte more flexibly.
- Remove struct ovs_action_push_nsh completely
- Add code to handle nested attribute for SET_MASKED
- Change PUSH_NSH to use the nested OVS_KEY_ATTR_NSH
to transfer NSH header data.
- Fix comments and coding style issues by Jiri and Eric
v1->v2
- Change encap_nsh and decap_nsh to push_nsh and pop_nsh
- Dynamically allocate struct ovs_action_push_nsh for
length-variable metadata.
OVS master and 2.8 branch has merged NSH userspace
patch series, this patch is to enable NSH support
in kernel data path in order that OVS can support
NSH in compat mode by porting this.
Signed-off-by: Yi Yang <yi.y.yang@intel.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Eric Garver <e@erig.me>
Acked-by: Pravin Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When we receive a packet on a QMI device in raw IP mode, we should call
skb_reset_mac_header() to ensure that skb->mac_header contains a valid
offset in the packet. While it shouldn't really matter, the packets have
no MAC header and the interface is configured as-such, it seems certain
parts of the network stack expects a "good" value in skb->mac_header.
Without the skb_reset_mac_header() call added in this patch, for example
shaping traffic (using tc) triggers the following oops on the first
received packet:
[ 303.642957] skbuff: skb_under_panic: text:8f137918 len:177 put:67 head:8e4b0f00 data:8e4b0eff tail:0x8e4b0fb0 end:0x8e4b1520 dev:wwan0
[ 303.655045] Kernel bug detected[#1]:
[ 303.658622] CPU: 1 PID: 1002 Comm: logd Not tainted 4.9.58 #0
[ 303.664339] task: 8fdf05e0 task.stack: 8f15c000
[ 303.668844] $ 0 : 00000000 00000001 0000007a 00000000
[ 303.674062] $ 4 : 8149a2fc 8149a2fc 8149ce20 00000000
[ 303.679284] $ 8 : 00000030 3878303a 31623465 20303235
[ 303.684510] $12 : ded731e3 2626a277 00000000 03bd0000
[ 303.689747] $16 : 8ef62b40 00000043 8f137918 804db5fc
[ 303.694978] $20 : 00000001 00000004 8fc13800 00000003
[ 303.700215] $24 : 00000001 8024ab10
[ 303.705442] $28 : 8f15c000 8fc19cf0 00000043 802cc920
[ 303.710664] Hi : 00000000
[ 303.713533] Lo : 74e58000
[ 303.716436] epc : 802cc920 skb_panic+0x58/0x5c
[ 303.721046] ra : 802cc920 skb_panic+0x58/0x5c
[ 303.725639] Status: 11007c03 KERNEL EXL IE
[ 303.729823] Cause : 50800024 (ExcCode 09)
[ 303.733817] PrId : 0001992f (MIPS 1004Kc)
[ 303.737892] Modules linked in: rt2800pci rt2800mmio rt2800lib qcserial ppp_async option usb_wwan rt2x00pci rt2x00mmio rt2x00lib rndis_host qmi_wwan ppp_generic nf_nat_pptp nf_conntrack_pptp nf_conntrack_ipv6 mt76x2i
Process logd (pid: 1002, threadinfo=8f15c000, task=8fdf05e0, tls=77b3eee4)
[ 303.962509] Stack : 00000000 80408990 8f137918 000000b1 00000043 8e4b0f00 8e4b0eff 8e4b0fb0
[ 303.970871] 8e4b1520 8fec1800 00000043 802cd2a4 6e000045 00000043 00000000 8ef62000
[ 303.979219] 8eef5d00 8ef62b40 8fea7300 8f137918 00000000 00000000 0002bb01 793e5664
[ 303.987568] 8ef08884 00000001 8fea7300 00000002 8fc19e80 8eef5d00 00000006 00000003
[ 303.995934] 00000000 8030ba90 00000003 77ab3fd0 8149dc80 8004d1bc 8f15c000 8f383700
[ 304.004324] ...
[ 304.006767] Call Trace:
[ 304.009241] [<802cc920>] skb_panic+0x58/0x5c
[ 304.013504] [<802cd2a4>] skb_push+0x78/0x90
[ 304.017783] [<8f137918>] 0x8f137918
[ 304.021269] Code: 00602825 0c02a3b4 24842888 <000c000d> 8c870060 8c8200a0 0007382b 00070336 8c88005c
[ 304.031034]
[ 304.032805] ---[ end trace b778c482b3f0bda9 ]---
[ 304.041384] Kernel panic - not syncing: Fatal exception in interrupt
[ 304.051975] Rebooting in 3 seconds..
While the oops is for a 4.9-kernel, I was able to trigger the same oops with
net-next as of yesterday.
Fixes: 32f7adf633b9 ("net: qmi_wwan: support "raw IP" mode")
Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com>
Acked-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The bonding miimon logic has a flaw, in that a failure of the
rtnl_trylock can cause a slave to become permanently stuck in
BOND_LINK_FAIL state.
The sequence of events to cause this is as follows:
1) bond_miimon_inspect finds that a slave's link is down, and so
calls bond_propose_link_state, setting slave->new_link_state to
BOND_LINK_FAIL, then sets slave->new_link to BOND_LINK_DOWN and returns
non-zero.
2) In bond_mii_monitor, the rtnl_trylock fails, and the timer is
rescheduled. No change is committed.
3) bond_miimon_inspect is called again, but this time the slave
from step 1 has recovered. slave->new_link is reset to NOCHANGE, and, as
slave->link was never changed, the switch enters the BOND_LINK_UP case,
and does nothing. The pending BOND_LINK_FAIL state from step 1 remains
pending, as new_link_state is not reset.
4) The state from step 3 persists until another slave changes link
state and causes bond_miimon_inspect to return non-zero. At this point,
the BOND_LINK_FAIL state change on the slave from steps 1-3 is committed,
and the slave will remain stuck in BOND_LINK_FAIL state even though it
is actually link up.
The remedy for this is to initialize new_link_state on each entry
to bond_miimon_inspect, as is already done with new_link.
Fixes: fb9eb899a6dc ("bonding: handle link transition from FAIL to UP correctly")
Reported-by: Alex Sidorenko <alexandre.sidorenko@hpe.com>
Reviewed-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Timestamps in pktgen are currently retrieved using the deprecated
do_gettimeofday() function that wraps its signed 32-bit seconds in 2038
(on 32-bit architectures) and requires a division operation to calculate
microseconds.
The pktgen header is also defined with the same limitations, hardcoding
to a 32-bit seconds field that can be interpreted as unsigned to produce
times that only wrap in 2106. Whatever code reads the timestamps should
be aware of that problem in general, but probably doesn't care too
much as we are mostly interested in the time passing between packets,
and that is correctly represented.
Using 64-bit nanoseconds would be cheaper and good for 584 years. Using
monotonic times would also make this unambiguous by avoiding the overflow,
but would make it harder to correlate to the times with those on remote
machines. Either approach would require adding a new runtime flag and
implementing the same thing on the remote side, which we probably don't
want to do unless someone sees it as a real problem. Also, this should
be coordinated with other pktgen implementations and might need a new
magic number.
For the moment, I'm documenting the overflow in the source code, and
changing the implementation over to an open-coded ktime_get_real_ts64()
plus division, so we don't have to look at it again while scanning for
deprecated time interfaces.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit adfa543e7314 ("dmatest: don't use set_freezable_with_signal()")
introduced a bug (that is in fact documented by the patch commit text)
that leaves behind a dangling pointer. Since the done_wait structure is
allocated on the stack, future invocations to the DMATEST can produce
undesirable results (e.g., corrupted spinlocks). Ideally, this would be
cleaned up in the thread handler, but at the very least, the kernel
is left in a very precarious scenario that can lead to some long debug
sessions when the crash comes later.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=197605
Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
|
|
This reverts commit 847449f23dcb: ("dmaengine: rcar-dmac: use TCRB instead
of TCR for residue") as it breaks small serial console.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
|
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Registering qrtr with module_init makes the ability of typical platform
code to create AF_QIPCRTR socket during probe a matter of link order
luck. Moving qrtr to postcore_initcall() avoids this.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains Netfilter/IPVS updates for your net-next
tree, they are:
1) Speed up table replacement on busy systems with large tables
(and many cores) in x_tables. Now xt_replace_table() synchronizes by
itself by waiting until all cpus had an even seqcount and we use no
use seqlock when fetching old counters, from Florian Westphal.
2) Add nf_l4proto_log_invalid() and nf_ct_l4proto_log_invalid() to speed
up packet processing in the fast path when logging is not enabled, from
Florian Westphal.
3) Precompute masked address from configuration plane in xt_connlimit,
from Florian.
4) Don't use explicit size for set selection if performance set policy
is selected.
5) Allow to get elements from an existing set in nf_tables.
6) Fix incorrect check in nft_hash_deactivate(), from Florian.
7) Cache netlink attribute size result in l4proto->nla_size, from
Florian.
8) Handle NFPROTO_INET in nf_ct_netns_get() from conntrack core.
9) Use power efficient workqueue in conntrack garbage collector, from
Vincent Guittot.
10) Remove unnecessary parameter, in conntrack l4proto functions, also
from Florian.
11) Constify struct nf_conntrack_l3proto definitions, from Florian.
12) Remove all typedefs in nf_conntrack_h323 via coccinelle semantic
patch, from Harsha Sharma.
13) Don't store address in the rbtree nodes in xt_connlimit, they are
never used, from Florian.
14) Fix out of bound access in the conntrack h323 helper, patch from
Eric Sesterhenn.
15) Print symbols for the address returned with %pS in IPVS, from
Helge Deller.
16) Proc output should only display its own netns in IPVS, from
KUWAZAWA Takuya.
17) Small clean up in size_entry_mwt(), from Colin Ian King.
18) Use test_and_clear_bit from nf_nat_proto_clean() instead of separated
non-atomic test and then clear bit, from Florian Westphal.
19) Consolidate prefix length maps in ipset, from Aaron Conole.
20) Fix sparse warnings in ipset, from Jozsef Kadlecsik.
21) Simplify list_set_memsize(), from simran singhal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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If source and destination bus width differs pack/unpack MDMA
feature has to be activated for alignment.
This pack/unpack feature implies to have both source/destination address
and buffer length aligned on bus width.
Fixes: a4ffb13c8946 ("dmaengine: Add STM32 MDMA driver")
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
|