BMC/Intel-BMC/linux.git/arch/powerpc/kernel, branch dev-4.10

pstore: Fix flags to enable dumps on powerpc

2017-05-20T12:31:04+00:00

commit 041939c1ec54208b42f5cd819209173d52a29d34 upstream. After commit c950fd6f201a kernel registers pstore write based on flag set. Pstore write for powerpc is broken as flags(PSTORE_FLAGS_DMESG) is not set for powerpc architecture. On panic, kernel doesn't write message to /fs/pstore/dmesg*(Entry doesn't gets created at all). This patch enables pstore write for powerpc architecture by setting PSTORE_FLAGS_DMESG flag. Fixes: c950fd6f201a ("pstore: Split pstore fragile flags") Signed-off-by: Ankit Kumar Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman

powerpc: Correctly disable latent entropy GCC plugin on prom_init.o

2017-05-14T12:08:20+00:00

commit eac6f8b0c7adb003776dbad9d037ee2fc64f9d62 upstream. Commit 38addce8b600 ("gcc-plugins: Add latent_entropy plugin") excludes certain powerpc early boot code from the latent entropy plugin by adding appropriate CFLAGS. It looks like this was supposed to cover prom_init.o, but ended up saying init.o (which doesn't exist) instead. Fix the typo. Fixes: 38addce8b600 ("gcc-plugins: Add latent_entropy plugin") Signed-off-by: Andrew Donnellan Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/kprobe: Fix oops when kprobed on 'stdu' instruction

2017-04-27T07:12:59+00:00

commit 9e1ba4f27f018742a1aa95d11e35106feba08ec1 upstream. If we set a kprobe on a 'stdu' instruction on powerpc64, we see a kernel OOPS: Bad kernel stack pointer cd93c840 at c000000000009868 Oops: Bad kernel stack pointer, sig: 6 [#1] ... GPR00: c000001fcd93cb30 00000000cd93c840 c0000000015c5e00 00000000cd93c840 ... NIP [c000000000009868] resume_kernel+0x2c/0x58 LR [c000000000006208] program_check_common+0x108/0x180 On a 64-bit system when the user probes on a 'stdu' instruction, the kernel does not emulate actual store in emulate_step() because it may corrupt the exception frame. So the kernel does the actual store operation in exception return code i.e. resume_kernel(). resume_kernel() loads the saved stack pointer from memory using lwz, which only loads the low 32-bits of the address, causing the kernel crash. Fix this by loading the 64-bit value instead. Fixes: be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") Signed-off-by: Ravi Bangoria Reviewed-by: Naveen N. Rao Reviewed-by: Ananth N Mavinakayanahalli [mpe: Change log massage, add stable tag] Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc: Don't try to fix up misaligned load-with-reservation instructions

2017-04-12T10:42:07+00:00

commit 48fe9e9488743eec9b7c1addd3c93f12f2123d54 upstream. In the past, there was only one load-with-reservation instruction, lwarx, and if a program attempted a lwarx on a misaligned address, it would take an alignment interrupt and the kernel handler would emulate it as though it was lwzx, which was not really correct, but benign since it is loading the right amount of data, and the lwarx should be paired with a stwcx. to the same address, which would also cause an alignment interrupt which would result in a SIGBUS being delivered to the process. We now have 5 different sizes of load-with-reservation instruction. Of those, lharx and ldarx cause an immediate SIGBUS by luck since their entries in aligninfo[] overlap instructions which were not fixed up, but lqarx overlaps with lhz and will be emulated as such. lbarx can never generate an alignment interrupt since it only operates on 1 byte. To straighten this out and fix the lqarx case, this adds code to detect the l[hwdq]arx instructions and return without fixing them up, resulting in a SIGBUS being delivered to the process. Signed-off-by: Paul Mackerras Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/64: Fix flush_(d|i)cache_range() called from modules

2017-04-12T10:42:07+00:00

commit 8f5f525d5b83f7d76a6baf9c4e94d4bf312ea7f6 upstream. When the kernel is compiled to use 64bit ABIv2 the _GLOBAL() macro does not include a global entry point. A function's global entry point is used when the function is called from a different TOC context and in the kernel this typically means a call from a module into the vmlinux (or vice-versa). There are a few exported asm functions declared with _GLOBAL() and calling them from a module will likely crash the kernel since any TOC relative load will yield garbage. flush_icache_range() and flush_dcache_range() are both exported to modules, and use the TOC, so must use _GLOBAL_TOC(). Fixes: 721aeaa9fdf3 ("powerpc: Build little endian ppc64 kernel with ABIv2") Signed-off-by: Oliver O'Halloran Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc: Disable HFSCR[TM] if TM is not supported

2017-04-12T10:42:07+00:00

commit 7ed23e1bae8bf7e37fd555066550a00b95a3a98b upstream. On Power8 & Power9 the early CPU inititialisation in __init_HFSCR() turns on HFSCR[TM] (Hypervisor Facility Status and Control Register [Transactional Memory]), but that doesn't take into account that TM might be disabled by CPU features, or disabled by the kernel being built with CONFIG_PPC_TRANSACTIONAL_MEM=n. So later in boot, when we have setup the CPU features, clear HSCR[TM] if the TM CPU feature has been disabled. We use CPU_FTR_TM_COMP to account for the CONFIG_PPC_TRANSACTIONAL_MEM=n case. Without this a KVM guest might try use TM, even if told not to, and cause an oops in the host kernel. Typically the oops is seen in __kvmppc_vcore_entry() and may or may not be fatal to the host, but is always bad news. In practice all shipping CPU revisions do support TM, and all host kernels we are aware of build with TM support enabled, so no one should actually be able to hit this in the wild. Fixes: 2a3563b023e5 ("powerpc: Setup in HFSCR for POWER8") Signed-off-by: Benjamin Herrenschmidt Tested-by: Sam Bobroff [mpe: Rewrite change log with input from Sam, add Fixes/stable] Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/64s: Fix idle wakeup potential to clobber registers

2017-03-30T07:44:06+00:00

commit 6d98ce0be541d4a3cfbb52cd75072c0339ebb500 upstream. We concluded there may be a window where the idle wakeup code could get to pnv_wakeup_tb_loss() (which clobbers non-volatile GPRs), but the hardware may set SRR1[46:47] to 01b (no state loss) which would result in the wakeup code failing to restore non-volatile GPRs. I was not able to trigger this condition with trivial tests on real hardware or simulator, but the ISA (at least 2.07) seems to allow for it, and Gautham says that it can happen if there is an exception pending when the sleep/winkle instruction is executed. Fixes: 1706567117ba ("powerpc/kvm: make hypervisor state restore a function") Signed-off-by: Nicholas Piggin Acked-by: Gautham R. Shenoy Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU

2017-03-12T05:44:20+00:00

commit fda2d27db6eae5c2468f9e4657539b72bbc238bb upstream. We will set LPCR with correct value for radix during int. This make sure we start with a sanitized value of LPCR. In case of kexec, cpus can have LPCR value based on the previous translation mode we were running. Fixes: fe036a0605d60 ("powerpc/64/kexec: Fix MMU cleanup on radix") Acked-by: Michael Neuling Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/xmon: Fix data-breakpoint

2017-03-12T05:44:20+00:00

commit c21a493a2b44650707d06741601894329486f2ad upstream. Currently xmon data-breakpoint feature is broken. Whenever there is a watchpoint match occurs, hw_breakpoint_handler will be called by do_break via notifier chains mechanism. If watchpoint is registered by xmon, hw_breakpoint_handler won't find any associated perf_event and returns immediately with NOTIFY_STOP. Similarly, do_break also returns without notifying to xmon. Solve this by returning NOTIFY_DONE when hw_breakpoint_handler does not find any perf_event associated with matched watchpoint, rather than NOTIFY_STOP, which tells the core code to continue calling the other breakpoint handlers including the xmon one. Signed-off-by: Ravi Bangoria Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

Merge tag 'powerpc-4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2017-02-03T19:10:06+00:00

Pull powerpc fixes from Michael Ellerman: "The main change is we're reverting the initial stack protector support we merged this cycle. It turns out to not work on toolchains built with libc support, and fixing it will be need to wait for another release. And the rest are all fairly minor: - Some pasemi machines were not booting due to a missing error check in prom_find_boot_cpu() - In EEH we were checking a pointer rather than the bool it pointed to - The clang build was broken by a BUILD_BUG_ON() we added. - The radix (Power9 only) version of map_kernel_page() was broken if our memory size was a multiple of 2MB, which it generally isn't Thanks to: Darren Stevens, Gavin Shan, Reza Arbab" * tag 'powerpc-4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/mm: Use the correct pointer when setting a 2MB pte powerpc: Fix build failure with clang due to BUILD_BUG_ON() powerpc: Revert the initial stack protector support powerpc/eeh: Fix wrong flag passed to eeh_unfreeze_pe() powerpc: Add missing error check to prom_find_boot_cpu()