kernel.git/arch/powerpc/xmon, branch linux-4.17.y

Merge branch 'topic/paca' into next

2018-03-30T22:09:36Z

Bring in yet another series that touches KVM code, and might need to be merged into the kvm-ppc branch to resolve conflicts. This required some changes in pnv_power9_force_smt4_catch/release() due to the paca array becomming an array of pointers.

powerpc/64: Use array of paca pointers and allocate pacas individually

2018-03-30T12:34:23Z

Change the paca array into an array of pointers to pacas. Allocate pacas individually. This allows flexibility in where the PACAs are allocated. Future work will allocate them node-local. Platforms that don't have address limits on PACAs would be able to defer PACA allocations until later in boot rather than allocate all possible ones up-front then freeing unused. This is slightly more overhead (one additional indirection) for cross CPU paca references, but those aren't too common. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

Merge branch 'topic/ppc-kvm' into next

2018-03-27T12:55:49Z

Merge the DAWR series, which touches arch code and KVM code and may need to be merged into the kvm-ppc tree.

powerpc: Update xmon to use ppc_breakpoint_available()

2018-03-27T12:55:11Z

The 'bd' command will now print an error and not set the breakpoint on P9. Signed-off-by: Michael Neuling [mpe: Unsplit quoted string] Signed-off-by: Michael Ellerman

powerpc/xmon: Move empty plpar_set_ciabr() into plpar_wrappers.h

2018-03-13T12:43:04Z

Now that plpar_wrappers.h has an #ifdef PSERIES we can move the empty version of plpar_set_ciabr() which xmon wants into there. Signed-off-by: Michael Ellerman

powerpc: Rename plapr routines to plpar

2018-03-13T12:43:04Z

Back in 2013 we added some hypercall wrappers which misspelled "plpar" (P-series Logical PARtition) as "plapr". Visually they're hard to distinguish and it almost doesn't matter, but it is confusing when grepping to miss some calls because of the typo. They've also started spreading, so before they take over let's fix them all to be "plpar". Signed-off-by: Michael Ellerman

powerpc/xmon: Clear all breakpoints when xmon is disabled via debugfs

2018-03-13T04:50:05Z

Presently when xmon is disabled by debugfs any existing instruction/data-access breakpoints set are not disabled. This may lead to kernel oops when those breakpoints are hit as the necessary debugger hooks aren't installed. Hence this patch introduces a new function named clear_all_bpt() which is called when xmon is disabled via debugfs. The function will unpatch/clear all the trap and ciabr/dab based breakpoints. Signed-off-by: Vaibhav Jain Reviewed-by: Balbir Singh [mpe: Fix build break when CONFIG_DEBUG_FS=n] Signed-off-by: Michael Ellerman

powerpc/xmon: Setup debugger hooks when first break-point is set

2018-03-13T04:10:16Z

Presently sysrq key for xmon('x') is registered during kernel init irrespective of the value of kernel param 'xmon'. Thus xmon is enabled even if 'xmon=off' is passed on the kernel command line. However this doesn't enable the kernel debugger hooks needed for instruction or data breakpoints. Thus when a break-point is hit with xmon=off a kernel oops of the form below is reported: Oops: Exception in kernel mode, sig: 5 [#1] < snip > Trace/breakpoint trap To fix this the patch checks and enables debugger hooks when an instruction or data break-point is set via xmon console. Signed-off-by: Vaibhav Jain Reviewed-by: Balbir Singh [mpe: Just printf directly, no need for static const char[]] Signed-off-by: Michael Ellerman

powerpc/64s: Improve RFI L1-D cache flush fallback

2018-01-23T05:16:33Z

The fallback RFI flush is used when firmware does not provide a way to flush the cache. It's a "displacement flush" that evicts useful data by displacing it with an uninteresting buffer. The flush has to take care to work with implementation specific cache replacment policies, so the recipe has been in flux. The initial slow but conservative approach is to touch all lines of a congruence class, with dependencies between each load. It has since been determined that a linear pattern of loads without dependencies is sufficient, and is significantly faster. Measuring the speed of a null syscall with RFI fallback flush enabled gives the relative improvement: P8 - 1.83x P9 - 1.75x The flush also becomes simpler and more adaptable to different cache geometries. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/xmon: Do not compute/store the major opcode

2018-01-21T12:37:43Z

In commit 5b102782c7f4 ("powerpc/xmon: Enable disassembly files (compilation changes)") usage of variable `op` has been removed. Completely remove opcode computation since not used anymore. Fix fatal warning: arch/powerpc/xmon/ppc-dis.c: In function ‘lookup_powerpc’: arch/powerpc/xmon/ppc-dis.c:96:17: error: variable ‘op’ set but not used [-Werror=unused-but-set-variable] unsigned long op; ^~ Signed-off-by: Mathieu Malaterre Signed-off-by: Michael Ellerman