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2018-01-27x86/speculation: Simplify indirect_branch_prediction_barrier()Borislav Petkov1-0/+6
Make it all a function which does the WRMSR instead of having a hairy inline asm. [dwmw2: export it, fix CONFIG_RETPOLINE issues] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: dave.hansen@intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1517070274-12128-4-git-send-email-dwmw@amazon.co.uk
2018-01-27x86/cpufeatures: Clean up Spectre v2 related CPUID flagsDavid Woodhouse2-14/+24
We want to expose the hardware features simply in /proc/cpuinfo as "ibrs", "ibpb" and "stibp". Since AMD has separate CPUID bits for those, use them as the user-visible bits. When the Intel SPEC_CTRL bit is set which indicates both IBRS and IBPB capability, set those (AMD) bits accordingly. Likewise if the Intel STIBP bit is set, set the AMD STIBP that's used for the generic hardware capability. Hide the rest from /proc/cpuinfo by putting "" in the comments. Including RETPOLINE and RETPOLINE_AMD which shouldn't be visible there. There are patches to make the sysfs vulnerabilities information non-readable by non-root, and the same should apply to all information about which mitigations are actually in use. Those *shouldn't* appear in /proc/cpuinfo. The feature bit for whether IBPB is actually used, which is needed for ALTERNATIVEs, is renamed to X86_FEATURE_USE_IBPB. Originally-by: Borislav Petkov <bp@suse.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: dave.hansen@intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1517070274-12128-2-git-send-email-dwmw@amazon.co.uk
2018-01-27x86/cpu/bugs: Make retpoline module warning conditionalThomas Gleixner1-3/+11
If sysfs is disabled and RETPOLINE not defined: arch/x86/kernel/cpu/bugs.c:97:13: warning: ‘spectre_v2_bad_module’ defined but not used [-Wunused-variable] static bool spectre_v2_bad_module; Hide it. Fixes: caf7501a1b4e ("module/retpoline: Warn about missing retpoline in module") Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org>
2018-01-26x86/bugs: Drop one "mitigation" from dmesgBorislav Petkov1-1/+1
Make [ 0.031118] Spectre V2 mitigation: Mitigation: Full generic retpoline into [ 0.031118] Spectre V2: Mitigation: Full generic retpoline to reduce the mitigation mitigations strings. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: riel@redhat.com Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: David Woodhouse <dwmw2@infradead.org> Cc: jikos@kernel.org Cc: luto@amacapital.net Cc: dave.hansen@intel.com Cc: torvalds@linux-foundation.org Cc: keescook@google.com Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: tim.c.chen@linux.intel.com Cc: pjt@google.com Link: https://lkml.kernel.org/r/20180126121139.31959-5-bp@alien8.de
2018-01-26x86/alternative: Print unadorned pointersBorislav Petkov1-7/+7
After commit ad67b74d2469 ("printk: hash addresses printed with %p") pointers are being hashed when printed. However, this makes the alternative debug output completely useless. Switch to %px in order to see the unadorned kernel pointers. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: riel@redhat.com Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: David Woodhouse <dwmw2@infradead.org> Cc: jikos@kernel.org Cc: luto@amacapital.net Cc: dave.hansen@intel.com Cc: torvalds@linux-foundation.org Cc: keescook@google.com Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Cc: pjt@google.com Link: https://lkml.kernel.org/r/20180126121139.31959-2-bp@alien8.de
2018-01-26x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) supportDavid Woodhouse1-1/+9
Expose indirect_branch_prediction_barrier() for use in subsequent patches. [ tglx: Add IBPB status to spectre_v2 sysfs file ] Co-developed-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Cc: gnomes@lxorguk.ukuu.org.uk Cc: ak@linux.intel.com Cc: ashok.raj@intel.com Cc: dave.hansen@intel.com Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1516896855-7642-8-git-send-email-dwmw@amazon.co.uk
2018-01-26x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodesDavid Woodhouse1-0/+66
This doesn't refuse to load the affected microcodes; it just refuses to use the Spectre v2 mitigation features if they're detected, by clearing the appropriate feature bits. The AMD CPUID bits are handled here too, because hypervisors *may* have been exposing those bits even on Intel chips, for fine-grained control of what's available. It is non-trivial to use x86_match_cpu() for this table because that doesn't handle steppings. And the approach taken in commit bd9240a18 almost made me lose my lunch. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: gnomes@lxorguk.ukuu.org.uk Cc: ak@linux.intel.com Cc: ashok.raj@intel.com Cc: dave.hansen@intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1516896855-7642-7-git-send-email-dwmw@amazon.co.uk
2018-01-26x86/pti: Do not enable PTI on CPUs which are not vulnerable to MeltdownDavid Woodhouse1-5/+43
Also, for CPUs which don't speculate at all, don't report that they're vulnerable to the Spectre variants either. Leave the cpu_no_meltdown[] match table with just X86_VENDOR_AMD in it for now, even though that could be done with a simple comparison, on the assumption that we'll have more to add. Based on suggestions from Dave Hansen and Alan Cox. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Dave Hansen <dave.hansen@intel.com> Cc: gnomes@lxorguk.ukuu.org.uk Cc: ak@linux.intel.com Cc: ashok.raj@intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1516896855-7642-6-git-send-email-dwmw@amazon.co.uk
2018-01-26x86/cpufeatures: Add CPUID_7_EDX CPUID leafDavid Woodhouse2-2/+1
This is a pure feature bits leaf. There are two AVX512 feature bits in it already which were handled as scattered bits, and three more from this leaf are going to be added for speculation control features. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: gnomes@lxorguk.ukuu.org.uk Cc: ak@linux.intel.com Cc: ashok.raj@intel.com Cc: dave.hansen@intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1516896855-7642-2-git-send-email-dwmw@amazon.co.uk
2018-01-26module/retpoline: Warn about missing retpoline in moduleAndi Kleen1-1/+16
There's a risk that a kernel which has full retpoline mitigations becomes vulnerable when a module gets loaded that hasn't been compiled with the right compiler or the right option. To enable detection of that mismatch at module load time, add a module info string "retpoline" at build time when the module was compiled with retpoline support. This only covers compiled C source, but assembler source or prebuilt object files are not checked. If a retpoline enabled kernel detects a non retpoline protected module at load time, print a warning and report it in the sysfs vulnerability file. [ tglx: Massaged changelog ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: gregkh@linuxfoundation.org Cc: torvalds@linux-foundation.org Cc: jeyu@kernel.org Cc: arjan@linux.intel.com Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
2018-01-24x86/centaur: Mark TSC invariantdavidwang1-0/+4
Centaur CPU has a constant frequency TSC and that TSC does not stop in C-States. But because the corresponding TSC feature flags are not set for that CPU, the TSC is treated as not constant frequency and assumed to stop in C-States, which makes it an unreliable and unusable clock source. Setting those flags tells the kernel that the TSC is usable, so it will select it over HPET. The effect of this is that reading time stamps (from kernel or user space) will be faster and more efficent. Signed-off-by: davidwang <davidwang@zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: qiyuanwang@zhaoxin.com Cc: linux-pm@vger.kernel.org Cc: brucechang@via-alliance.com Cc: cooperyan@zhaoxin.com Cc: benjaminpan@viatech.com Link: https://lkml.kernel.org/r/1516616057-5158-1-git-send-email-davidwang@zhaoxin.com
2018-01-24x86/microcode: Fix again accessing initrd after having been freedBorislav Petkov1-1/+1
Commit 24c2503255d3 ("x86/microcode: Do not access the initrd after it has been freed") fixed attempts to access initrd from the microcode loader after it has been freed. However, a similar KASAN warning was reported (stack trace edited): smpboot: Booting Node 0 Processor 1 APIC 0x11 ================================================================== BUG: KASAN: use-after-free in find_cpio_data+0x9b5/0xa50 Read of size 1 at addr ffff880035ffd000 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.8-slack #7 Hardware name: System manufacturer System Product Name/A88X-PLUS, BIOS 3003 03/10/2016 Call Trace: dump_stack print_address_description kasan_report ? find_cpio_data __asan_report_load1_noabort find_cpio_data find_microcode_in_initrd __load_ucode_amd load_ucode_amd_ap load_ucode_ap After some investigation, it turned out that a merge was done using the wrong side to resolve, leading to picking up the previous state, before the 24c2503255d3 fix. Therefore the Fixes tag below contains a merge commit. Revert the mismerge by catching the save_microcode_in_initrd_amd() retval and thus letting the function exit with the last return statement so that initrd_gone can be set to true. Fixes: f26483eaedec ("Merge branch 'x86/urgent' into x86/microcode, to resolve conflicts") Reported-by: <higuita@gmx.net> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=198295 Link: https://lkml.kernel.org/r/20180123104133.918-2-bp@alien8.de
2018-01-24x86/microcode/intel: Extend BDW late-loading further with LLC size checkJia Zhang1-2/+18
Commit b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check") reduced the impact of erratum BDF90 for Broadwell model 79. The impact can be reduced further by checking the size of the last level cache portion per core. Tony: "The erratum says the problem only occurs on the large-cache SKUs. So we only need to avoid the update if we are on a big cache SKU that is also running old microcode." For more details, see erratum BDF90 in document #334165 (Intel Xeon Processor E7-8800/4800 v4 Product Family Specification Update) from September 2017. Fixes: b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check") Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1516321542-31161-1-git-send-email-zhang.jia@linux.alibaba.com
2018-01-23ftrace, orc, x86: Handle ftrace dynamically allocated trampolinesSteven Rostedt (VMware)1-1/+47
The function tracer can create a dynamically allocated trampoline that is called by the function mcount or fentry hook that is used to call the function callback that is registered. The problem is that the orc undwinder will bail if it encounters one of these trampolines. This breaks the stack trace of function callbacks, which include the stack tracer and setting the stack trace for individual functions. Since these dynamic trampolines are basically copies of the static ftrace trampolines defined in ftrace_*.S, we do not need to create new orc entries for the dynamic trampolines. Finding the return address on the stack will be identical as the functions that were copied to create the dynamic trampolines. When encountering a ftrace dynamic trampoline, we can just use the orc entry of the ftrace static function that was copied for that trampoline. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23x86/ftrace: Fix ORC unwinding from ftrace handlersJosh Poimboeuf2-10/+19
Steven Rostedt discovered that the ftrace stack tracer is broken when it's used with the ORC unwinder. The problem is that objtool is instructed by the Makefile to ignore the ftrace_64.S code, so it doesn't generate any ORC data for it. Fix it by making the asm code objtool-friendly: - Objtool doesn't like the fact that save_mcount_regs pushes RBP at the beginning, but it's never restored (directly, at least). So just skip the original RBP push, which is only needed for frame pointers anyway. - Annotate some functions as normal callable functions with ENTRY/ENDPROC. - Add an empty unwind hint to return_to_handler(). The return address isn't on the stack, so there's nothing ORC can do there. It will just punt in the unlikely case it tries to unwind from that code. With all that fixed, remove the OBJECT_FILES_NON_STANDARD Makefile annotation so objtool can read the file. Link: http://lkml.kernel.org/r/20180123040746.ih4ep3tk4pbjvg7c@treble Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23mm/memory_failure: Remove unused trapno from memory_failureEric W. Biederman1-3/+3
Today 4 architectures set ARCH_SUPPORTS_MEMORY_FAILURE (arm64, parisc, powerpc, and x86), while 4 other architectures set __ARCH_SI_TRAPNO (alpha, metag, sparc, and tile). These two sets of architectures do not interesect so remove the trapno paramater to remove confusion. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-21Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds3-1/+33
Pull x86 pti fixes from Thomas Gleixner: "A small set of fixes for the meltdown/spectre mitigations: - Make kprobes aware of retpolines to prevent probes in the retpoline thunks. - Make the machine check exception speculation protected. MCE used to issue an indirect call directly from the ASM entry code. Convert that to a direct call into a C-function and issue the indirect call from there so the compiler can add the retpoline protection, - Make the vmexit_fill_RSB() assembly less stupid - Fix a typo in the PTI documentation" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Optimize inline assembler for vmexit_fill_RSB x86/pti: Document fix wrong index kprobes/x86: Disable optimizing on the function jumps to indirect thunk kprobes/x86: Blacklist indirect thunk functions for kprobes retpoline: Introduce start/end markers of indirect thunk x86/mce: Make machine check speculation protected
2018-01-20x86/jailhouse: Respect pci=lastbus command line settingsJan Kiszka1-1/+3
Limiting the scan width to the known last bus via the command line can accelerate the boot noteworthy. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jailhouse <jailhouse-dev@googlegroups.com> Link: https://lkml.kernel.org/r/51f5fe62-ca8f-9286-5cdb-39df3fad78b4@siemens.com
2018-01-20x86/jailhouse: Set X86_FEATURE_TSC_KNOWN_FREQJan Kiszka1-0/+1
Otherwise, Linux will not recognize precalibrated_tsc_khz and disable the tsc as clocksource. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jailhouse <jailhouse-dev@googlegroups.com> Link: https://lkml.kernel.org/r/975fbfc9-2a64-cc56-40d5-164992ec3916@siemens.com
2018-01-19kprobes/x86: Disable optimizing on the function jumps to indirect thunkMasami Hiramatsu1-1/+22
Since indirect jump instructions will be replaced by jump to __x86_indirect_thunk_*, those jmp instruction must be treated as an indirect jump. Since optprobe prohibits to optimize probes in the function which uses an indirect jump, it also needs to find out the function which jump to __x86_indirect_thunk_* and disable optimization. Add a check that the jump target address is between the __indirect_thunk_start/end when optimizing kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/151629212062.10241.6991266100233002273.stgit@devbox
2018-01-19retpoline: Introduce start/end markers of indirect thunkMasami Hiramatsu1-0/+6
Introduce start/end markers of __x86_indirect_thunk_* functions. To make it easy, consolidate .text.__x86.indirect_thunk.* sections to one .text.__x86.indirect_thunk section and put it in the end of kernel text section and adds __indirect_thunk_start/end so that other subsystem (e.g. kprobes) can identify it. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/151629206178.10241.6828804696410044771.stgit@devbox
2018-01-19x86/mce: Make machine check speculation protectedThomas Gleixner1-0/+5
The machine check idtentry uses an indirect branch directly from the low level code. This evades the speculation protection. Replace it by a direct call into C code and issue the indirect call there so the compiler can apply the proper speculation protection. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by:Borislav Petkov <bp@alien8.de> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Niced-by: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801181626290.1847@nanos
2018-01-18x86/mm: Rework wbinvd, hlt operation in stop_this_cpu()Tom Lendacky1-10/+15
Some issues have been reported with the for loop in stop_this_cpu() that issues the 'wbinvd; hlt' sequence. Reverting this sequence to halt() has been shown to resolve the issue. However, the wbinvd is needed when running with SME. The reason for the wbinvd is to prevent cache flush races between encrypted and non-encrypted entries that have the same physical address. This can occur when kexec'ing from memory encryption active to inactive or vice-versa. The important thing is to not have outside of kernel text memory references (such as stack usage), so the usage of the native_*() functions is needed since these expand as inline asm sequences. So instead of reverting the change, rework the sequence. Move the wbinvd instruction outside of the for loop as native_wbinvd() and make its execution conditional on X86_FEATURE_SME. In the for loop, change the asm 'wbinvd; hlt' sequence back to a halt sequence but use the native_halt() call. Fixes: bba4ed011a52 ("x86/mm, kexec: Allow kexec to be used with SME") Reported-by: Dave Young <dyoung@redhat.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Dave Young <dyoung@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Yu Chen <yu.c.chen@intel.com> Cc: Baoquan He <bhe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: kexec@lists.infradead.org Cc: ebiederm@redhat.com Cc: Borislav Petkov <bp@alien8.de> Cc: Rui Zhang <rui.zhang@intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180117234141.21184.44067.stgit@tlendack-t1.amdoffice.net
2018-01-18x86/intel_rdt: Add command line parameter to control L2_CDPFenghua Yu1-0/+2
L2 CDP can be controlled by kernel parameter "rdt=". If "rdt=l2cdp", L2 CDP is turned on. If "rdt=!l2cdp", L2 CDP is turned off. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: Vikas" <vikas.shivappa@intel.com> Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com> Cc: Reinette" <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1513810644-78015-7-git-send-email-fenghua.yu@intel.com
2018-01-18x86/intel_rdt: Enable L2 CDP in MSR IA32_L2_QOS_CFGFenghua Yu2-26/+94
Bit 0 in MSR IA32_L2_QOS_CFG (0xc82) is L2 CDP enable bit. By default, the bit is zero, i.e. L2 CAT is enabled, and L2 CDP is disabled. When the resctrl mount parameter "cdpl2" is given, the bit is set to 1 and L2 CDP is enabled. In L2 CDP mode, the L2 CAT mask MSRs are re-mapped into interleaved pairs of mask MSRs for code (referenced by an odd CLOSID) and data (referenced by an even CLOSID). Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: Vikas" <vikas.shivappa@intel.com> Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com> Cc: Reinette" <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1513810644-78015-6-git-send-email-fenghua.yu@intel.com
2018-01-18x86/intel_rdt: Add two new resources for L2 Code and Data Prioritization (CDP)Fenghua Yu2-10/+58
L2 data and L2 code are added as new resources in rdt_resources_all[] and data in the resources are configured. When L2 CDP is enabled, the schemata will have the two resources in this format: L2DATA:l2id0=xxxx;l2id1=xxxx;.... L2CODE:l2id0=xxxx;l2id1=xxxx;.... xxxx represent CBM (Cache Bit Mask) values in the schemata, similar to all others (L2 CAT/L3 CAT/L3 CDP). Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: Vikas" <vikas.shivappa@intel.com> Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com> Cc: Reinette" <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1513810644-78015-5-git-send-email-fenghua.yu@intel.com
2018-01-18x86/intel_rdt: Enumerate L2 Code and Data Prioritization (CDP) featureFenghua Yu1-0/+1
L2 Code and Data Prioritization (CDP) is enumerated in CPUID(EAX=0x10, ECX=0x2):ECX.bit2 Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: Vikas" <vikas.shivappa@intel.com> Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com> Cc: Reinette" <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1513810644-78015-4-git-send-email-fenghua.yu@intel.com
2018-01-18Merge branches 'acpi-x86', 'acpi-apei' and 'acpi-ec'Rafael J. Wysocki1-18/+17
* acpi-x86: ACPI / x86: boot: Propagate error code in acpi_gsi_to_irq() ACPI / x86: boot: Don't setup SCI on HW-reduced platforms ACPI / x86: boot: Use INVALID_ACPI_IRQ instead of 0 for acpi_sci_override_gsi ACPI / x86: boot: Get rid of ACPI_INVALID_GSI ACPI / x86: boot: Swap variables in condition in acpi_register_gsi_ioapic() * acpi-apei: ACPI / APEI: remove redundant variables len and node_len ACPI: APEI: call into AER handling regardless of severity ACPI: APEI: handle PCIe AER errors in separate function * acpi-ec: ACPI: EC: Fix debugfs_create_*() usage
2018-01-18Merge branches 'acpi-pm' and 'pm-sleep'Rafael J. Wysocki1-0/+2
* acpi-pm: platform/x86: surfacepro3: Support for wakeup from suspend-to-idle ACPI / PM: Use Low Power S0 Idle on more systems ACPI / PM: Make it possible to ignore the system sleep blacklist * pm-sleep: PM / hibernate: Drop unused parameter of enough_swap block, scsi: Fix race between SPI domain validation and system suspend PM / sleep: Make lock/unlock_system_sleep() available to kernel modules PM: hibernate: Do not subtract NR_FILE_MAPPED in minimum_image_size()
2018-01-18BackMerge tag 'v4.15-rc8' into drm-nextDave Airlie41-315/+790
Linux 4.15-rc8 Daniel requested this for so the intel CI won't fall over on drm-next so often.
2018-01-17Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds8-25/+77
Pull x86 fixes from Ingo Molnar: "Misc fixes: - A rather involved set of memory hardware encryption fixes to support the early loading of microcode files via the initrd. These are larger than what we normally take at such a late -rc stage, but there are two mitigating factors: 1) much of the changes are limited to the SME code itself 2) being able to early load microcode has increased importance in the post-Meltdown/Spectre era. - An IRQ vector allocator fix - An Intel RDT driver use-after-free fix - An APIC driver bug fix/revert to make certain older systems boot again - A pkeys ABI fix - TSC calibration fixes - A kdump fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/vector: Fix off by one in error path x86/intel_rdt/cqm: Prevent use after free x86/mm: Encrypt the initrd earlier for BSP microcode update x86/mm: Prepare sme_encrypt_kernel() for PAGE aligned encryption x86/mm: Centralize PMD flags in sme_encrypt_kernel() x86/mm: Use a struct to reduce parameters for SME PGD mapping x86/mm: Clean up register saving in the __enc_copy() assembly code x86/idt: Mark IDT tables __initconst Revert "x86/apic: Remove init_bsp_APIC()" x86/mm/pkeys: Fix fill_sig_info_pkey x86/tsc: Print tsc_khz, when it differs from cpu_khz x86/tsc: Fix erroneous TSC rate on Skylake Xeon x86/tsc: Future-proof native_calibrate_tsc() kdump: Write the correct address of mem_section into vmcoreinfo
2018-01-17Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-1/+36
Pull x86 pti bits and fixes from Thomas Gleixner: "This last update contains: - An objtool fix to prevent a segfault with the gold linker by changing the invocation order. That's not just for gold, it's a general robustness improvement. - An improved error message for objtool which spares tearing hairs. - Make KASAN fail loudly if there is not enough memory instead of oopsing at some random place later - RSB fill on context switch to prevent RSB underflow and speculation through other units. - Make the retpoline/RSB functionality work reliably for both Intel and AMD - Add retpoline to the module version magic so mismatch can be detected - A small (non-fix) update for cpufeatures which prevents cpu feature clashing for the upcoming extra mitigation bits to ease backporting" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: module: Add retpoline tag to VERMAGIC x86/cpufeature: Move processor tracing out of scattered features objtool: Improve error message for bad file argument objtool: Fix seg fault with gold linker x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros x86/retpoline: Fill RSB on context switch for affected CPUs x86/kasan: Panic if there is not enough memory to boot
2018-01-17x86/apic/vector: Fix off by one in error pathThomas Gleixner1-2/+5
Keith reported the following warning: WARNING: CPU: 28 PID: 1420 at kernel/irq/matrix.c:222 irq_matrix_remove_managed+0x10f/0x120 x86_vector_free_irqs+0xa1/0x180 x86_vector_alloc_irqs+0x1e4/0x3a0 msi_domain_alloc+0x62/0x130 The reason for this is that if the vector allocation fails the error handling code tries to free the failed vector as well, which causes the above imbalance warning to trigger. Adjust the error path to handle this correctly. Fixes: b5dc8e6c21e7 ("x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors") Reported-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Keith Busch <keith.busch@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161217300.1823@nanos
2018-01-17x86/intel_rdt/cqm: Prevent use after freeThomas Gleixner1-4/+4
intel_rdt_iffline_cpu() -> domain_remove_cpu() frees memory first and then proceeds accessing it. BUG: KASAN: use-after-free in find_first_bit+0x1f/0x80 Read of size 8 at addr ffff883ff7c1e780 by task cpuhp/31/195 find_first_bit+0x1f/0x80 has_busy_rmid+0x47/0x70 intel_rdt_offline_cpu+0x4b4/0x510 Freed by task 195: kfree+0x94/0x1a0 intel_rdt_offline_cpu+0x17d/0x510 Do the teardown first and then free memory. Fixes: 24247aeeabe9 ("x86/intel_rdt/cqm: Improve limbo list processing") Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Peter Zilstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: "Roderick W. Smith" <rod.smith@canonical.com> Cc: 1733662@bugs.launchpad.net Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161957510.2366@nanos
2018-01-17x86/cpufeature: Move processor tracing out of scattered featuresPaolo Bonzini1-1/+0
Processor tracing is already enumerated in word 9 (CPUID[7,0].EBX), so do not duplicate it in the scattered features word. Besides being more tidy, this will be useful for KVM when it presents processor tracing to the guests. KVM selects host features that are supported by both the host kernel (depending on command line options, CPU errata, or whatever) and KVM. Whenever a full feature word exists, KVM's code is written in the expectation that the CPUID bit number matches the X86_FEATURE_* bit number, but this is not the case for X86_FEATURE_INTEL_PT. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luwei Kang <luwei.kang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/1516117345-34561-1-git-send-email-pbonzini@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16Merge branch 'sev-v9-p2' of https://github.com/codomania/kvmPaolo Bonzini2-20/+47
This part of Secure Encrypted Virtualization (SEV) patch series focuses on KVM changes required to create and manage SEV guests. SEV is an extension to the AMD-V architecture which supports running encrypted virtual machine (VMs) under the control of a hypervisor. Encrypted VMs have their pages (code and data) secured such that only the guest itself has access to unencrypted version. Each encrypted VM is associated with a unique encryption key; if its data is accessed to a different entity using a different key the encrypted guest's data will be incorrectly decrypted, leading to unintelligible data. This security model ensures that hypervisor will no longer able to inspect or alter any guest code or data. The key management of this feature is handled by a separate processor known as the AMD Secure Processor (AMD-SP) which is present on AMD SOCs. The SEV Key Management Specification (see below) provides a set of commands which can be used by hypervisor to load virtual machine keys through the AMD-SP driver. The patch series adds a new ioctl in KVM driver (KVM_MEMORY_ENCRYPT_OP). The ioctl will be used by qemu to issue SEV guest-specific commands defined in Key Management Specification. The following links provide additional details: AMD Memory Encryption white paper: http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf AMD64 Architecture Programmer's Manual: http://support.amd.com/TechDocs/24593.pdf SME is section 7.10 SEV is section 15.34 SEV Key Management: http://support.amd.com/TechDocs/55766_SEV-KM API_Specification.pdf KVM Forum Presentation: http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf SEV Guest BIOS support: SEV support has been add to EDKII/OVMF BIOS https://github.com/tianocore/edk2 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-16KVM: X86: use paravirtualized TLB ShootdownWanpeng Li1-0/+47
Remote TLB flush does a busy wait which is fine in bare-metal scenario. But with-in the guest, the vcpus might have been pre-empted or blocked. In this scenario, the initator vcpu would end up busy-waiting for a long amount of time; it also consumes CPU unnecessarily to wake up the target of the shootdown. This patch set adds support for KVM's new paravirtualized TLB flush; remote TLB flush does not wait for vcpus that are sleeping, instead KVM will flush the TLB as soon as the vCPU starts running again. The improvement is clearly visible when the host is overcommitted; in this case, the PV TLB flush (in addition to avoiding the wait on the main CPU) prevents preempted vCPUs from stealing precious execution time from the running ones. Testing on a Xeon Gold 6142 2.6GHz 2 sockets, 32 cores, 64 threads, so 64 pCPUs, and each VM is 64 vCPUs. ebizzy -M vanilla optimized boost 1VM 46799 48670 4% 2VM 23962 42691 78% 3VM 16152 37539 132% Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-01-16KVM: X86: Add KVM_VCPU_PREEMPTEDWanpeng Li1-1/+1
The next patch will add another bit to the preempted field in kvm_steal_time. Define a constant for bit 0 (the only one that is currently used). Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-01-16x86/platform/UV: Fix GAM MMR references in the UV x2apic codeMike Travis1-46/+37
Along with the fixes in UV4A (rev2) MMRs, the code to access those MMRs also was modified by the fixes. UV3, UV4, and UV4A no longer have compatible setups for Global Address Memory (GAM). Correct the new mistakes. Signed-off-by: Mike Travis <mike.travis@hpe.com> Acked-by: Andrew Banman <abanman@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dimitri Sivanich <sivanich@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515440405-20880-6-git-send-email-mike.travis@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/platform/UV: Add references to access fixed UV4A HUB MMRsMike Travis1-0/+2
Add references to enable access to fixed UV4A (rev2) HUB MMRs. Signed-off-by: Mike Travis <mike.travis@hpe.com> Acked-by: Andrew Banman <abanman@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dimitri Sivanich <sivanich@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515440405-20880-4-git-send-email-mike.travis@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16x86/platform/UV: Fix UV4A support on new Intel ProcessorsMike Travis1-3/+11
Upcoming Intel CascadeLake and IceLake processors have some architecture changes that required fixes in the UV4 HUB bringing that chip to revision 2. The nomenclature for that new chip is "UV4A". This patch fixes the references for the expanded MMR definitions in the previous (automated) patch. Signed-off-by: Mike Travis <mike.travis@hpe.com> Acked-by: Andrew Banman <abanman@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dimitri Sivanich <sivanich@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515440405-20880-3-git-send-email-mike.travis@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-15signal: Unify and correct copy_siginfo_to_user32Eric W. Biederman1-94/+2
Among the existing architecture specific versions of copy_siginfo_to_user32 there are several different implementation problems. Some architectures fail to handle all of the cases in in the siginfo union. Some architectures perform a blind copy of the siginfo union when the si_code is negative. A blind copy suggests the data is expected to be in 32bit siginfo format, which means that receiving such a signal via signalfd won't work, or that the data is in 64bit siginfo and the code is copying nonsense to userspace. Create a single instance of copy_siginfo_to_user32 that all of the architectures can share, and teach it to handle all of the cases in the siginfo union correctly, with the assumption that siginfo is stored internally to the kernel is 64bit siginfo format. A special case is made for x86 x32 format. This is needed as presence of both x32 and ia32 on x86_64 results in two different 32bit signal formats. By allowing this small special case there winds up being exactly one code base that needs to be maintained between all of the architectures. Vastly increasing the testing base and the chances of finding bugs. As the x86 copy of copy_siginfo_to_user32 the call of the x86 signal_compat_build_tests were moved into sigaction_compat_abi, so that they will keep running. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-16x86/mm: Encrypt the initrd earlier for BSP microcode updateTom Lendacky2-12/+2
Currently the BSP microcode update code examines the initrd very early in the boot process. If SME is active, the initrd is treated as being encrypted but it has not been encrypted (in place) yet. Update the early boot code that encrypts the kernel to also encrypt the initrd so that early BSP microcode updates work. Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180110192634.6026.10452.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-15signal: Unify and correct copy_siginfo_from_user32Eric W. Biederman1-21/+0
The function copy_siginfo_from_user32 is used for two things, in ptrace since the dawn of siginfo for arbirarily modifying a signal that user space sees, and in sigqueueinfo to send a signal with arbirary siginfo data. Create a single copy of copy_siginfo_from_user32 that all architectures share, and teach it to handle all of the cases in the siginfo union. In the generic version of copy_siginfo_from_user32 ensure that all of the fields in siginfo are initialized so that the siginfo structure can be safely copied to userspace if necessary. When copying the embedded sigval union copy the si_int member. That ensures the 32bit values passes through the kernel unchanged. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-15signal/ia64: Move the ia64 specific si_codes to asm-generic/siginfo.hEric W. Biederman1-2/+2
Having si_codes in many different files simply encourages duplicate definitions that can cause problems later. To avoid that merge the ia64 specific si_codes into uapi/asm-generic/siginfo.h Update the sanity checks in arch/x86/kernel/signal_compat.c to expect the now lager NSIGILL and NSIGFPE. As nothing excpe the larger count is exposed on x86 no additional code needs to be updated. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-15signal: unify compat_siginfo_tAl Viro1-0/+4
--EWB Added #ifdef CONFIG_X86_X32_ABI to arch/x86/kernel/signal_compat.c Changed #ifdef CONFIG_X86_X32 to #ifdef CONFIG_X86_X32_ABI in linux/compat.h CONFIG_X86_X32 is set when the user requests X32 support. CONFIG_X86_X32_ABI is set when the user requests X32 support and the tool-chain has X32 allowing X32 support to be built. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2018-01-15x86/jailhouse: Hide x2apic code when CONFIG_X86_X2APIC=nThomas Gleixner1-14/+19
x2apic_phys is not available when CONFIG_X86_X2APIC=n and the code is not optimized out resulting in a build fail: jailhouse.c: In function ‘jailhouse_get_smp_config’: jailhouse.c:73:3: error: ‘x2apic_phys’ undeclared (first use in this function) Fixes: 11c8dc419bbc ("x86/jailhouse: Enable APIC and SMP support") Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: jailhouse-dev@googlegroups.com
2018-01-15swiotlb: rename swiotlb_free to swiotlb_exitChristoph Hellwig1-1/+1
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian König <christian.koenig@amd.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-01-15x86: rename swiotlb_dma_opsChristoph Hellwig1-2/+2
We'll need that name for a generic implementation soon. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian König <christian.koenig@amd.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-01-15dma-mapping: add an arch_dma_supported hookChristoph Hellwig1-7/+12
To implement the x86 forbid_dac and iommu_sac_force we want an arch hook so that it can apply the global options across all dma_map_ops implementations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>