linux/arch, branch v3.2.48

x86/efi: Fix dummy variable buffer allocation

2013-06-29T03:06:32Z

commit b8cb62f82103083a6e8fa5470bfe634a2c06514d upstream. 1. Check for allocation failure 2. Clear the buffer contents, as they may actually be written to flash 3. Don't leak the buffer Compile-tested only. [ Tested successfully on my buggy ASUS machine - Matt ] Signed-off-by: Ben Hutchings Signed-off-by: Matt Fleming

Modify UEFI anti-bricking code

2013-06-29T03:06:32Z

commit f8b8404337de4e2466e2e1139ea68b1f8295974f upstream. This patch reworks the UEFI anti-bricking code, including an effective reversion of cc5a080c and 31ff2f20. It turns out that calling QueryVariableInfo() from boot services results in some firmware implementations jumping to physical addresses even after entering virtual mode, so until we have 1:1 mappings for UEFI runtime space this isn't going to work so well. Reverting these gets us back to the situation where we'd refuse to create variables on some systems because they classify deleted variables as "used" until the firmware triggers a garbage collection run, which they won't do until they reach a lower threshold. This results in it being impossible to install a bootloader, which is unhelpful. Feedback from Samsung indicates that the firmware doesn't need more than 5KB of storage space for its own purposes, so that seems like a reasonable threshold. However, there's still no guarantee that a platform will attempt garbage collection merely because it drops below this threshold. It seems that this is often only triggered if an attempt to write generates a genuine EFI_OUT_OF_RESOURCES error. We can force that by attempting to create a variable larger than the remaining space. This should fail, but if it somehow succeeds we can then immediately delete it. I've tested this on the UEFI machines I have available, but I don't have a Samsung and so can't verify that it avoids the bricking problem. Signed-off-by: Matthew Garrett Signed-off-by: Lee, Chun-Y [ dummy variable cleanup ] Signed-off-by: Matt Fleming [bwh: Backported to 3.2: the reverted changes were never applied here] Signed-off-by: Ben Hutchings

x86: fix build error and kconfig for ia32_emulation and binfmt

2013-06-29T03:06:30Z

commit d1603990ea626668c78527376d9ec084d634202d upstream. Fix kconfig warning and build errors on x86_64 by selecting BINFMT_ELF when COMPAT_BINFMT_ELF is being selected. warning: (IA32_EMULATION) selects COMPAT_BINFMT_ELF which has unmet direct dependencies (COMPAT && BINFMT_ELF) fs/built-in.o: In function `elf_core_dump': compat_binfmt_elf.c:(.text+0x3e093): undefined reference to `elf_core_extra_phdrs' compat_binfmt_elf.c:(.text+0x3ebcd): undefined reference to `elf_core_extra_data_size' compat_binfmt_elf.c:(.text+0x3eddd): undefined reference to `elf_core_write_extra_phdrs' compat_binfmt_elf.c:(.text+0x3f004): undefined reference to `elf_core_write_extra_data' [ hpa: This was sent to me for -next but it is a low risk build fix ] Signed-off-by: Randy Dunlap Link: http://lkml.kernel.org/r/51C0B614.5000708@infradead.org Signed-off-by: H. Peter Anvin Signed-off-by: Ben Hutchings

KVM: x86: remove vcpu's CPL check in host-invoked XCR set

2013-06-29T03:06:29Z

commit 764bcbc5a6d7a2f3e75c9f0e4caa984e2926e346 upstream. __kvm_set_xcr function does the CPL check when set xcr. __kvm_set_xcr is called in two flows, one is invoked by guest, call stack shown as below, handle_xsetbv(or xsetbv_interception) kvm_set_xcr __kvm_set_xcr the other one is invoked by host, for example during system reset: kvm_arch_vcpu_ioctl kvm_vcpu_ioctl_x86_set_xcrs __kvm_set_xcr The former does need the CPL check, but the latter does not. Signed-off-by: Zhang Haoyu [Tweaks to commit message. - Paolo] Signed-off-by: Paolo Bonzini Signed-off-by: Ben Hutchings

ARM: 7772/1: Fix missing flush_kernel_dcache_page() for noMMU

2013-06-29T03:06:28Z

commit 63384fd0b1509acf522a8a8fcede09087eedb7df upstream. Commit 1bc3974 (ARM: 7755/1: handle user space mapped pages in flush_kernel_dcache_page) moved the implementation of flush_kernel_dcache_page() into mm/flush.c but did not implement it on noMMU ARM. Signed-off-by: Simon Baatz Acked-by: Kevin Hilman Signed-off-by: Russell King Signed-off-by: Ben Hutchings

ARM: 7755/1: handle user space mapped pages in flush_kernel_dcache_page

2013-06-29T03:06:28Z

commit 1bc39742aab09248169ef9d3727c9def3528b3f3 upstream. Commit f8b63c1 made flush_kernel_dcache_page a no-op assuming that the pages it needs to handle are kernel mapped only. However, for example when doing direct I/O, pages with user space mappings may occur. Thus, continue to do lazy flushing if there are no user space mappings. Otherwise, flush the kernel cache lines directly. Signed-off-by: Simon Baatz Reviewed-by: Catalin Marinas Signed-off-by: Russell King Signed-off-by: Ben Hutchings

tilepro: work around module link error with gcc 4.7

2013-06-29T03:06:25Z

commit 3cb3f839d306443f3d1e79b0bde1a2ad2c12b555 upstream. gcc 4.7.x is emitting calls to __ffsdi2 where previously it used to inline the appropriate ctz instructions. While this needs to be fixed in gcc, it's also easy to avoid having it cause build failures when building with those compilers by exporting __ffsdi2 to modules. Signed-off-by: Chris Metcalf Signed-off-by: Ben Hutchings

powerpc: Fix emulation of illegal instructions on PowerNV platform

2013-06-19T01:17:02Z

commit bf593907f7236e95698a76b7c7a2bbf8b1165327 upstream. Normally, the kernel emulates a few instructions that are unimplemented on some processors (e.g. the old dcba instruction), or privileged (e.g. mfpvr). The emulation of unimplemented instructions is currently not working on the PowerNV platform. The reason is that on these machines, unimplemented and illegal instructions cause a hypervisor emulation assist interrupt, rather than a program interrupt as on older CPUs. Our vector for the emulation assist interrupt just calls program_check_exception() directly, without setting the bit in SRR1 that indicates an illegal instruction interrupt. This fixes it by making the emulation assist interrupt set that bit before calling program_check_interrupt(). With this, old programs that use no-longer implemented instructions such as dcba now work again. Signed-off-by: Paul Mackerras Signed-off-by: Benjamin Herrenschmidt [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

x86: Fix typo in kexec register clearing

2013-06-19T01:17:02Z

commit c8a22d19dd238ede87aa0ac4f7dbea8da039b9c1 upstream. Fixes a typo in register clearing code. Thanks to PaX Team for fixing this originally, and James Troup for pointing it out. Signed-off-by: Kees Cook Link: http://lkml.kernel.org/r/20130605184718.GA8396@www.outflux.net Cc: PaX Team Signed-off-by: H. Peter Anvin Signed-off-by: Ben Hutchings

ARM: 7743/1: compressed/head.S: work around new binutils warning

2013-06-19T01:16:56Z

commit da94a829305f1c217cfdf6771cb1faca0917e3b9 upstream. In August 2012, Matthew Gretton-Dann checked a change into binutils labelled "Error on obsolete & warn on deprecated registers", apparently as part of ARMv8 support. Apparently, this was supposed to emit the message "Warning: This coprocessor register access is deprecated in ARMv8" when using certain mcr/mrc instructions and building for ARMv8. Unfortunately, the message that is actually emitted appears to be '(null)', which is less helpful in comparison. Even more unfortunately, this is biting us on every single kernel build with a new gas, because arch/arm/boot/compressed/head.S and some other files in that directory are built with -march=all since kernel commit 80cec14a8 "[ARM] Add -march=all to assembly file build in arch/arm/boot/compressed" back in v2.6.28. This patch reverts Russell's nice solution and instead marks the head.S file to be built for armv7-a, which fortunately lets us build all instructions in that file without warnings even on the broken binutils. Without this patch, building anything results in: arch/arm/boot/compressed/head.S: Assembler messages: arch/arm/boot/compressed/head.S:565: Warning: (null) arch/arm/boot/compressed/head.S:676: Warning: (null) arch/arm/boot/compressed/head.S:698: Warning: (null) arch/arm/boot/compressed/head.S:722: Warning: (null) arch/arm/boot/compressed/head.S:726: Warning: (null) arch/arm/boot/compressed/head.S:957: Warning: (null) arch/arm/boot/compressed/head.S:996: Warning: (null) arch/arm/boot/compressed/head.S:997: Warning: (null) arch/arm/boot/compressed/head.S:1027: Warning: (null) arch/arm/boot/compressed/head.S:1035: Warning: (null) arch/arm/boot/compressed/head.S:1046: Warning: (null) arch/arm/boot/compressed/head.S:1060: Warning: (null) arch/arm/boot/compressed/head.S:1092: Warning: (null) arch/arm/boot/compressed/head.S:1094: Warning: (null) arch/arm/boot/compressed/head.S:1095: Warning: (null) arch/arm/boot/compressed/head.S:1102: Warning: (null) arch/arm/boot/compressed/head.S:1134: Warning: (null) Signed-off-by: Arnd Bergmann Cc: Matthew Gretton-Dann Signed-off-by: Russell King [bwh: Backported to 3.2: - Adjust context - Remove definition of asflags-y as it is now empty] Signed-off-by: Ben Hutchings