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| | * | | | | | | | | | | | | | x86_64, entry: Use sysret to return to userspace when possibleAndy Lutomirski2015-02-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x86_64 entry code currently jumps through complex and inconsistent hoops to try to minimize the impact of syscall exit work. For a true fast-path syscall, almost nothing needs to be done, so returning is just a check for exit work and sysret. For a full slow-path return from a syscall, the C exit hook is invoked if needed and we join the iret path. Using iret to return to userspace is very slow, so the entry code has accumulated various special cases to try to do certain forms of exit work without invoking iret. This is error-prone, since it duplicates assembly code paths, and it's dangerous, since sysret can malfunction in interesting ways if used carelessly. It's also inefficient, since a lot of useful cases aren't optimized and therefore force an iret out of a combination of paranoia and the fact that no one has bothered to write even more asm code to avoid it. I would argue that this approach is backwards. Rather than trying to avoid the iret path, we should instead try to make the iret path fast. Under a specific set of conditions, iret is unnecessary. In particular, if RIP==RCX, RFLAGS==R11, RIP is canonical, RF is not set, and both SS and CS are as expected, then movq 32(%rsp),%rsp;sysret does the same thing as iret. This set of conditions is nearly always satisfied on return from syscalls, and it can even occasionally be satisfied on return from an irq. Even with the careful checks for sysret applicability, this cuts nearly 80ns off of the overhead from syscalls with unoptimized exit work. This includes tracing and context tracking, and any return that invokes KVM's user return notifier. For example, the cost of getpid with CONFIG_CONTEXT_TRACKING_FORCE=y drops from ~360ns to ~280ns on my computer. This may allow the removal and even eventual conversion to C of a respectable amount of exit asm. This may require further tweaking to give the full benefit on Xen. It may be worthwhile to adjust signal delivery and exec to try hit the sysret path. This does not optimize returns to 32-bit userspace. Making the same optimization for CS == __USER32_CS is conceptually straightforward, but it will require some tedious code to handle the differences between sysretl and sysexitl. Link: http://lkml.kernel.org/r/71428f63e681e1b4aa1a781e3ef7c27f027d1103.1421453410.git.luto@amacapital.net Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86, traps: Fix ist_enter from userspaceAndy Lutomirski2015-02-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | context_tracking_user_exit() has no effect if in_interrupt() returns true, so ist_enter() didn't work. Fix it by calling exception_enter(), and thus context_tracking_user_exit(), before incrementing the preempt count. This also adds an assertion that will catch the problem reliably if CONFIG_PROVE_RCU=y to help prevent the bug from being reintroduced. Link: http://lkml.kernel.org/r/261ebee6aee55a4724746d0d7024697013c40a08.1422709102.git.luto@amacapital.net Fixes: 959274753857 x86, traps: Track entry into and exit from IST context Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| * | | | | | | | | | | | | | | Merge tag 'pr-20150201-x86-vdso' of ↵Ingo Molnar2015-02-03
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/asm Pull VDSO fix fro Andy Lutomirski: "x86, vdso: One trivial last-minute VDSO build improvement Andrey noticed that the VDSO build wasn't cleaning itself up. This one-liner fixes it." Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | | | | | | | | | | x86, vdso: teach 'make clean' remove vdso64 binariesAndrey Skvortsov2015-01-28
| | | |_|_|_|_|_|_|_|_|_|/ / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After 'make clean' vdso64.so and vdso64.dbg.so were left in arch/x86/vdso/. Link: http://lkml.kernel.org/r/1422453867-17326-1-git-send-email-andrej.skvortzov@gmail.com Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| * | | | | | | | | | | | | | | Merge tag 'v3.19-rc7' into x86/asm, to refresh the branch before pulling in ↵Ingo Molnar2015-02-03
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | |_|/ / / / / / / / / / / / / | |/| | | | | | | | / / / / / / | | | |_|_|_|_|_|_|/ / / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | | | | | | Merge tag 'pr-20150114-x86-entry' of ↵Ingo Molnar2015-01-28
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/asm Pull x86/entry enhancements from Andy Lutomirski: " This is my accumulated x86 entry work, part 1, for 3.20. The meat of this is an IST rework. When an IST exception interrupts user space, we will handle it on the per-thread kernel stack instead of on the IST stack. This sounds messy, but it actually simplifies the IST entry/exit code, because it eliminates some ugly games we used to play in order to handle rescheduling, signal delivery, etc on the way out of an IST exception. The IST rework introduces proper context tracking to IST exception handlers. I haven't seen any bug reports, but the old code could have incorrectly treated an IST exception handler as an RCU extended quiescent state. The memory failure change (included in this pull request with Borislav and Tony's permission) eliminates a bunch of code that is no longer needed now that user memory failure handlers are called in process context. Finally, this includes a few on Denys' uncontroversial and Obviously Correct (tm) cleanups. The IST and memory failure changes have been in -next for a while. LKML references: IST rework: http://lkml.kernel.org/r/cover.1416604491.git.luto@amacapital.net Memory failure change: http://lkml.kernel.org/r/54ab2ffa301102cd6e@agluck-desk.sc.intel.com Denys' cleanups: http://lkml.kernel.org/r/1420927210-19738-1-git-send-email-dvlasenk@redhat.com " This tree semantically depends on and is based on the following RCU commit: 734d16801349 ("rcu: Make rcu_nmi_enter() handle nesting") ... and for that reason won't be pushed upstream before the RCU bits hit Linus's tree. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | | | | | | | | | x86: entry_64.S: fold SAVE_ARGS_IRQ macro into its sole userDenys Vlasenko2015-01-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No code changes. This is a preparatory patch for change in "struct pt_regs" handling. CC: Linus Torvalds <torvalds@linux-foundation.org> CC: Oleg Nesterov <oleg@redhat.com> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Andy Lutomirski <luto@amacapital.net> CC: Frederic Weisbecker <fweisbec@gmail.com> CC: X86 ML <x86@kernel.org> CC: Alexei Starovoitov <ast@plumgrid.com> CC: Will Drewry <wad@chromium.org> CC: Kees Cook <keescook@chromium.org> CC: linux-kernel@vger.kernel.org Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86: ia32entry.S: fix wrong symbolic constant usage: R11->ARGOFFSETDenys Vlasenko2015-01-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The values of these two constants are the same, the meaning is different. Acked-by: Borislav Petkov <bp@suse.de> CC: Linus Torvalds <torvalds@linux-foundation.org> CC: Oleg Nesterov <oleg@redhat.com> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Borislav Petkov <bp@alien8.de> CC: Frederic Weisbecker <fweisbec@gmail.com> CC: X86 ML <x86@kernel.org> CC: Alexei Starovoitov <ast@plumgrid.com> CC: Will Drewry <wad@chromium.org> CC: Kees Cook <keescook@chromium.org> CC: linux-kernel@vger.kernel.org Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86: entry_64.S: delete unused codeDenys Vlasenko2015-01-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A define, two macros and an unreferenced bit of assembly are gone. Acked-by: Borislav Petkov <bp@suse.de> CC: Linus Torvalds <torvalds@linux-foundation.org> CC: Oleg Nesterov <oleg@redhat.com> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Andy Lutomirski <luto@amacapital.net> CC: Frederic Weisbecker <fweisbec@gmail.com> CC: X86 ML <x86@kernel.org> CC: Alexei Starovoitov <ast@plumgrid.com> CC: Will Drewry <wad@chromium.org> CC: Kees Cook <keescook@chromium.org> CC: linux-kernel@vger.kernel.org Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86, mce: Get rid of TIF_MCE_NOTIFY and associated mce tricksLuck, Tony2015-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now switch to the kernel stack when a machine check interrupts during user mode. This means that we can perform recovery actions in the tail of do_machine_check() Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86, traps: Add ist_begin_non_atomic and ist_end_non_atomicAndy Lutomirski2015-01-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some IST handlers, if the interrupt came from user mode, we can safely enable preemption. Add helpers to do it safely. This is intended to be used my the memory failure code in do_machine_check. Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86: Clean up current_stack_pointerAndy Lutomirski2015-01-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no good reason for it to be a macro, and x86_64 will want to use it, so it should be in a header. Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86, traps: Track entry into and exit from IST contextAndy Lutomirski2015-01-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently pretend that IST context is like standard exception context, but this is incorrect. IST entries from userspace are like standard exceptions except that they use per-cpu stacks, so they are atomic. IST entries from kernel space are like NMIs from RCU's perspective -- they are not quiescent states even if they interrupted the kernel during a quiescent state. Add and use ist_enter and ist_exit to track IST context. Even though x86_32 has no IST stacks, we track these interrupts the same way. This fixes two issues: - Scheduling from an IST interrupt handler will now warn. It would previously appear to work as long as we got lucky and nothing overwrote the stack frame. (I don't know of any bugs in this that would trigger the warning, but it's good to be on the safe side.) - RCU handling in IST context was dangerous. As far as I know, only machine checks were likely to trigger this, but it's good to be on the safe side. Note that the machine check handlers appears to have been missing any context tracking at all before this patch. Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| | * | | | | | | | | | | | | | x86, entry: Switch stacks on a paranoid entry from userspaceAndy Lutomirski2015-01-02
| | | |_|_|_|/ / / / / / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This causes all non-NMI, non-double-fault kernel entries from userspace to run on the normal kernel stack. Double-fault is exempt to minimize confusion if we double-fault directly from userspace due to a bad kernel stack. This is, suprisingly, simpler and shorter than the current code. It removes the IMO rather frightening paranoid_userspace path, and it make sync_regs much simpler. There is no risk of stack overflow due to this change -- the kernel stack that we switch to is empty. This will also enable us to create non-atomic sections within machine checks from userspace, which will simplify memory failure handling. It will also allow the upcoming fsgsbase code to be simplified, because it doesn't need to worry about usergs when scheduling in paranoid_exit, as that code no longer exists. Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Tony Luck <tony.luck@intel.com> Acked-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Andy Lutomirski <luto@amacapital.net>
| * | | | | | | | | | | | | | Merge commit 3669ef9fa7d3 ("x86, tls: Interpret an all-zero struct user_desc ↵Ingo Molnar2015-01-28
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | as 'no segment'") into x86/asm Pick up the latestest asm fixes before advancing it any further. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | | | | | | | x86_64 entry: Fix RCX for ptraced syscallsAndy Lutomirski2015-01-17
| | |_|_|_|/ / / / / / / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The int_ret_from_sys_call and syscall tracing code disagrees with the sysret path as to the value of RCX. The Intel SDM, the AMD APM, and my laptop all agree that sysret returns with RCX == RIP. The syscall tracing code does not respect this property. For example, this program: int main() { extern const char syscall_rip[]; unsigned long rcx = 1; unsigned long orig_rcx = rcx; asm ("mov $-1, %%eax\n\t" "syscall\n\t" "syscall_rip:" : "+c" (rcx) : : "r11"); printf("syscall: RCX = %lX RIP = %lX orig RCX = %lx\n", rcx, (unsigned long)syscall_rip, orig_rcx); return 0; } prints: syscall: RCX = 400556 RIP = 400556 orig RCX = 1 Running it under strace gives this instead: syscall: RCX = FFFFFFFFFFFFFFFF RIP = 400556 orig RCX = 1 This changes FIXUP_TOP_OF_STACK to match sysret, causing the test to show RCX == RIP even under strace. It looks like this is a partial revert of: 88e4bc32686e ("[PATCH] x86-64 architecture specific sync for 2.5.8") from the historic git tree. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/c9a418c3dc3993cb88bb7773800225fd318a4c67.1421453410.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | | | | | | | | | | | Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds2015-02-09
|\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Ingo Molnar: "Continued fallout of the conversion of the x86 IRQ code to the hierarchical irqdomain framework: more cleanups, simplifications, memory allocation behavior enhancements, mainly in the interrupt remapping and APIC code" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) x86, init: Fix UP boot regression on x86_64 iommu/amd: Fix irq remapping detection logic x86/acpi: Make acpi_[un]register_gsi_ioapic() depend on CONFIG_X86_LOCAL_APIC x86: Consolidate boot cpu timer setup x86/apic: Reuse apic_bsp_setup() for UP APIC setup x86/smpboot: Sanitize uniprocessor init x86/smpboot: Move apic init code to apic.c init: Get rid of x86isms x86/apic: Move apic_init_uniprocessor code x86/smpboot: Cleanup ioapic handling x86/apic: Sanitize ioapic handling x86/ioapic: Add proper checks to setp/enable_IO_APIC() x86/ioapic: Provide stub functions for IOAPIC%3Dn x86/smpboot: Move smpboot inlines to code x86/x2apic: Use state information for disable x86/x2apic: Split enable and setup function x86/x2apic: Disable x2apic from nox2apic setup x86/x2apic: Add proper state tracking x86/x2apic: Clarify remapping mode for x2apic enablement x86/x2apic: Move code in conditional region ...
| * | | | | | | | | | | | | | | x86, init: Fix UP boot regression on x86_64Thomas Gleixner2015-01-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 30b8b0066caf "init: Get rid of x86isms" broke the UP boot on x86_64. That happens because CONFIG_UP_LATE_INIT depends on CONFIG_X86_UP_APIC. X86_UP_APIC is a 32bit only config switch and therefor not set on 64bit UP builds. As a consequence the UP init of the local APIC and the IOAPIC is not called, which results in a boot failure. Make it depend on !SMP && X86_LOCAL_APIC instead. Fixes: 30b8b0066caf init: Get rid of x86isms Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/acpi: Make acpi_[un]register_gsi_ioapic() depend on CONFIG_X86_LOCAL_APICThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Get rid of the defined but not used warnings Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com>
| * | | | | | | | | | | | | | | x86: Consolidate boot cpu timer setupThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the APIC bringup is consolidated we can move the setup call for the percpu clock event device to apic_bsp_setup(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211704.162567839@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Reuse apic_bsp_setup() for UP APIC setupThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extend apic_bsp_setup() so the same code flow can be used for APIC_init_uniprocessor(). Folded Jiangs fix to provide proper ordering of the UP setup. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211704.084765674@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/smpboot: Sanitize uniprocessor initThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The UP related setups for local apic are mangled into smp_sanity_check(). That results in duplicate calls to disable_smp() and makes the code hard to follow. Let smp_sanity_check() return dedicated values for the various exit reasons and handle them at the call site. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.987833932@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/smpboot: Move apic init code to apic.cThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We better provide proper functions which implement the required code flow in the apic code rather than letting the smpboot code open code it. That allows to make more functions static and confines the APIC functionality to apic.c where it belongs. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.907616730@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | init: Get rid of x86ismsThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The UP local API support can be set up from an early initcall. No need for horrible hackery in the init code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.827943883@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Move apic_init_uniprocessor codeThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the code to a different place so we can make other functions inline. Preparatory patch for further cleanups. No change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.731329006@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/smpboot: Cleanup ioapic handlingThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | smpboot is very creative with the ways to disable ioapic. smpboot_clear_io_apic() smpboot_clear_io_apic_irqs() and disable_ioapic_support() serve a similar purpose. smpboot_clear_io_apic_irqs() is the most useless of all functions as it clears a variable which has not been setup yet. Aside of that it has the same ifdef mess and conditionals around the ioapic related code, which can now be removed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.650280684@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Sanitize ioapic handlingThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have proper stubs for the IOAPIC=n case and the setup/enable function have the required checks inside now. Remove the ifdeffery and the copy&pasted conditionals. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>C Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.569830549@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/ioapic: Add proper checks to setp/enable_IO_APIC()Thomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No point to have the same checks at every call site. Add them to the functions, so they can be called unconditionally. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.490719938@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/ioapic: Provide stub functions for IOAPIC%3DnThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To avoid lots of ifdeffery provide proper stubs for setup_IO_APIC(), enable_IO_APIC() and setup_ioapic_dest(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.397170414@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/smpboot: Move smpboot inlines to codeThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No point for a separate header file. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.304126687@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/x2apic: Use state information for disableThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the state information to simplify the disable logic further. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.209387598@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/x2apic: Split enable and setup functionThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | enable_x2apic() is a convoluted unreadable mess because it is used for both enablement in early boot and for setup in cpu_init(). Split the code into x2apic_enable() for enablement and x2apic_setup() for setup of (secondary cpus). Make use of the new state tracking to simplify the logic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.129287153@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/x2apic: Disable x2apic from nox2apic setupThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no point in postponing the hardware disablement of x2apic. It can be disabled right away in the nox2apic setup function. Disable it right away and set the state to DISABLED . This allows to remove all the nox2apic conditionals all over the place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.051214090@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/x2apic: Add proper state trackingThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having 3 different variables to track the state is just silly and error prone. Add a proper state tracking variable which covers the three possible states: ON/OFF/DISABLED. We cannot use x2apic_mode for this as this would require to change all users of x2apic_mode with explicit comparisons for a state value instead of treating it as boolean. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211702.955392443@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/x2apic: Clarify remapping mode for x2apic enablementThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename the argument of try_to_enable_x2apic() so the purpose becomes more clear. Make the pr_warning more consistent and avoid the double print of "disabling". Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211702.876012628@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/x2apic: Move code in conditional regionThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No point in having try_to_enable_x2apic() outside of the CONFIG_X86_X2APIC section and having inline functions and more ifdefs to deal with it. Move the code into the existing ifdef section and remove the inline cruft. Fixup the printk about not enabling interrupt remapping as suggested by Boris. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211702.795388613@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Check x2apic earlyThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No point in delaying the x2apic detection for the CONFIG_X86_X2APIC=n case to enable_IR_x2apic(). We rather detect that before we try to setup anything there. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211702.702479404@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Make disable x2apic work reallyThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If x2apic_preenabled is not enabled, then disable_x2apic() is not called from various places which results in x2apic_disabled not being set. So other code pathes can happily reenable the x2apic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211702.621431109@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/ioapic: Check x2apic reallyThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x2apic_preenabled flag is just a horrible hack and if X2APIC support is disabled it does not reflect the actual hardware state. Check the hardware instead. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211702.541280622@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Move x2apic code to one placeThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having several disjunct pieces of code for x2apic support makes reading the code unnecessarily hard. Move it to one ifdeffed section. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211702.445212133@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Make x2apic_mode depend on CONFIG_X86_X2APICThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No point in having a static variable around which is always 0. Let the compiler optimize code out if disabled. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211702.363274310@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Avoid open coded x2apic detectionThomas Gleixner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | enable_IR_x2apic() grew a open coded x2apic detection. Implement a proper helper function which shares the code with the already existing x2apic_enabled(). Made it use rdmsrl_safe as suggested by Boris. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211702.285038186@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | iommu/irq_remapping: Kill function irq_remapping_supported() and related codeJiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Simplify irq_remapping code by killing irq_remapping_supported() and related interfaces. Joerg posted a similar patch at https://lkml.org/lkml/2014/12/15/490, so assume an signed-off from Joerg. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Tested-by: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-14-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Only disable CPU x2apic mode when necessaryJiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When interrupt remapping hardware is not in X2APIC, CPU X2APIC mode will be disabled if: 1) Maximum CPU APIC ID is bigger than 255 2) hypervisior doesn't support x2apic mode. But we should only check whether hypervisor supports X2APIC mode when hypervisor(CONFIG_HYPERVISOR_GUEST) is enabled, otherwise X2APIC will always be disabled when CONFIG_HYPERVISOR_GUEST is disabled and IR doesn't work in X2APIC mode. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Tested-by: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-12-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Handle XAPIC remap mode proper.Jiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If remapping is in XAPIC mode, the setup code just skips X2APIC initialization without checking max CPU APIC ID in system, which may cause problem if system has a CPU with APIC ID bigger than 255. Handle IR in XAPIC mode the same way as if remapping is disabled. [ tglx: Split out from previous patch ] Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-8-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Refine enable_IR_x2apic() and related functionsJiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refine enable_IR_x2apic() and related functions for better readability. [ tglx: Removed the XAPIC mode change and split it out into a seperate patch. Added comments. ] Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-8-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Correctly detect X2APIC status in function enable_IR()Jiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | X2APIC will be disabled if user specifies "nox2apic" on kernel command line, even when x2apic_preenabled is true. So correctly detect X2APIC status by using x2apic_enabled() instead of x2apic_preenabled. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-7-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Kill useless variable x2apic_enabled in function enable_IR_x2apic()Jiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Local variable x2apic_enabled has been assigned to but never referred, so kill it. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-6-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Panic if kernel doesn't support x2apic but BIOS has enabled x2apicJiang Liu2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When kernel doesn't support X2APIC but BIOS has enabled X2APIC, system may panic or hang without useful messages. On the other hand, it's hard to dynamically disable X2APIC when CONFIG_X86_X2APIC is disabled. So panic with a clear message in such a case. Now system panics as below when X2APIC is disabled and interrupt remapping is enabled: [ 0.316118] LAPIC pending interrupts after 512 EOI [ 0.322126] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 [ 0.368655] Kernel panic - not syncing: timer doesn't work through Interrupt-remapped IO-APIC [ 0.378300] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.18.0+ #340 [ 0.385300] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRIVTIN1.86B.0051.L05.1406240953 06/24/2014 [ 0.396997] ffff88046dc03000 ffff88046c307dd8 ffffffff8179dada 00000000000043f2 [ 0.405629] ffffffff81a92158 ffff88046c307e58 ffffffff8179b757 0000000000000002 [ 0.414261] 0000000000000008 ffff88046c307e68 ffff88046c307e08 ffffffff813ad82b [ 0.422890] Call Trace: [ 0.425711] [<ffffffff8179dada>] dump_stack+0x45/0x57 [ 0.431533] [<ffffffff8179b757>] panic+0xc1/0x1f5 [ 0.436978] [<ffffffff813ad82b>] ? delay_tsc+0x3b/0x70 [ 0.442910] [<ffffffff8166fa2c>] panic_if_irq_remap+0x1c/0x20 [ 0.449524] [<ffffffff81d73645>] setup_IO_APIC+0x405/0x82e [ 0.464979] [<ffffffff81d6fcc2>] native_smp_prepare_cpus+0x2d9/0x31c [ 0.472274] [<ffffffff81d5d0ac>] kernel_init_freeable+0xd6/0x223 [ 0.479170] [<ffffffff81792ad0>] ? rest_init+0x80/0x80 [ 0.485099] [<ffffffff81792ade>] kernel_init+0xe/0xf0 [ 0.490932] [<ffffffff817a537c>] ret_from_fork+0x7c/0xb0 [ 0.497054] [<ffffffff81792ad0>] ? rest_init+0x80/0x80 [ 0.502983] ---[ end Kernel panic - not syncing: timer doesn't work through Interrupt-remapped IO-APIC System hangs as below when X2APIC and interrupt remapping are both disabled: [ 1.102782] pci 0000:00:02.0: System wakeup disabled by ACPI [ 1.109351] pci 0000:00:03.0: System wakeup disabled by ACPI [ 1.115915] pci 0000:00:03.2: System wakeup disabled by ACPI [ 1.122479] pci 0000:00:03.3: System wakeup disabled by ACPI [ 1.132274] pci 0000:00:1c.0: Enabling MPC IRBNCE [ 1.137620] pci 0000:00:1c.0: Intel PCH root port ACS workaround enabled [ 1.145239] pci 0000:00:1c.0: System wakeup disabled by ACPI [ 1.151790] pci 0000:00:1c.7: Enabling MPC IRBNCE [ 1.157128] pci 0000:00:1c.7: Intel PCH root port ACS workaround enabled [ 1.164748] pci 0000:00:1c.7: System wakeup disabled by ACPI [ 1.171447] pci 0000:00:1e.0: System wakeup disabled by ACPI [ 1.178612] acpiphp: Slot [8] registered [ 1.183095] pci 0000:00:02.0: PCI bridge to [bus 01] [ 1.188867] acpiphp: Slot [2] registered With this patch applied, the system panics in both cases with a proper panic message. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com> Link: http://lkml.kernel.org/r/1420615903-28253-5-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | | | | | | | | | | x86/apic: Clear stale x2apic modeThomas Gleixner2015-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If x2apic got disabled on the kernel command line, then the following issue can happen: enable_IR_x2apic() .... x2apic_mode = 1; enable_x2apic(); if (x2apic_disabled) { __disable_x2apic(); return; } That leaves X2APIC disabled in hardware, but x2apic_mode stays 1. So all other code which checks x2apic_mode gets the wrong information. Set x2apic_mode to 0 after disabling it in hardware. This is just a hotfix. The proper solution is to rework this code so it has seperate functions for the initial setup on the boot processor and the secondary cpus, but that's beyond the scope of this fix. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Oren Twaig <oren@scalemp.com>