kernel.git/arch/sparc, branch linux-4.12.y

sparc64: remove unnecessary log message

2017-08-30T08:26:22Z

[ Upstream commit 6170a506899aee3dd4934c928426505e47b1b466 ] There is no need to log message if ATU hvapi couldn't get register. Unlike PCI hvapi, ATU hvapi registration failure is not hard error. Even if ATU hvapi registration fails (on system with ATU or without ATU) system continues with legacy IOMMU. So only log message when ATU hvapi successfully get registered. Signed-off-by: Tushar Dave Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix exception handling in UltraSPARC-III memcpy.

2017-08-11T15:34:00Z

[ Upstream commit 0ede1c401332173ab0693121dc6cde04a4dbf131 ] Mikael Pettersson reported that some test programs in the strace-4.18 testsuite cause an OOPS. After some debugging it turns out that garbage values are returned when an exception occurs, causing the fixup memset() to be run with bogus arguments. The problem is that two of the exception handler stubs write the successfully copied length into the wrong register. Fixes: ee841d0aff64 ("sparc64: Convert U3copy_{from,to}_user to accurate exception reporting.") Reported-by: Mikael Pettersson Tested-by: Mikael Pettersson Reviewed-by: Sam Ravnborg Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Register hugepages during arch init

2017-08-11T15:34:00Z

[ Upstream commit 8399e4b88a93fc7bc00fff3b8da9b2e718b7f45e ] Add hstate for each supported hugepage size using arch initcall. This change fixes some hugepage parameter parsing inconsistencies: case 1: no hugepage parameters Without hugepage parameters, only a hugepages-8192kB entry is visible in sysfs. It's different from x86_64 where both 2M and 1G hugepage sizes are available. case 2: default_hugepagesz=[64K|256M|2G] When specifying only a default_hugepagesz parameter, the default hugepage size isn't really changed and it stays at 8M. This is again different from x86_64. Orabug: 25869946 Reviewed-by: Bob Picco Signed-off-by: Nitin Gupta Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Prevent perf from running during super critical sections

2017-08-11T15:34:00Z

[ Upstream commit fc290a114fc6034b0f6a5a46e2fb7d54976cf87a ] This fixes another cause of random segfaults and bus errors that may occur while running perf with the callgraph option. Critical sections beginning with spin_lock_irqsave() raise the interrupt level to PIL_NORMAL_MAX (14) and intentionally do not block performance counter interrupts, which arrive at PIL_NMI (15). But some sections of code are "super critical" with respect to perf because the perf_callchain_user() path accesses user space and may cause TLB activity as well as faults as it unwinds the user stack. One particular critical section occurs in switch_mm: spin_lock_irqsave(&mm->context.lock, flags); ... load_secondary_context(mm); tsb_context_switch(mm); ... spin_unlock_irqrestore(&mm->context.lock, flags); If a perf interrupt arrives in between load_secondary_context() and tsb_context_switch(), then perf_callchain_user() could execute with the context ID of one process, but with an active TSB for a different process. When the user stack is accessed, it is very likely to incur a TLB miss, since the h/w context ID has been changed. The TLB will then be reloaded with a translation from the TSB for one process, but using a context ID for another process. This exposes memory from one process to another, and since it is a mapping for stack memory, this usually causes the new process to crash quickly. This super critical section needs more protection than is provided by spin_lock_irqsave() since perf interrupts must not be allowed in. Since __tsb_context_switch already goes through the trouble of disabling interrupts completely, we fix this by moving the secondary context load down into this better protected region. Orabug: 25577560 Signed-off-by: Dave Aldridge Signed-off-by: Rob Gardner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Measure receiver forward progress to avoid send mondo timeout

2017-08-11T15:33:59Z

[ Upstream commit 9d53caec84c7c5700e7c1ed744ea584fff55f9ac ] A large sun4v SPARC system may have moments of intensive xcall activities, usually caused by unmapping many pages on many CPUs concurrently. This can flood receivers with CPU mondo interrupts for an extended period, causing some unlucky senders to hit send-mondo timeout. This problem gets worse as cpu count increases because sometimes mappings must be invalidated on all CPUs, and sometimes all CPUs may gang up on a single CPU. But a busy system is not a broken system. In the above scenario, as long as the receiver is making forward progress processing mondo interrupts, the sender should continue to retry. This patch implements the receiver's forward progress meter by introducing a per cpu counter 'cpu_mondo_counter[cpu]' where 'cpu' is in the range of 0..NR_CPUS. The receiver increments its counter as soon as it receives a mondo and the sender tracks the receiver's counter. If the receiver has stopped making forward progress when the retry limit is reached, the sender declares send-mondo-timeout and panic; otherwise, the receiver is allowed to keep making forward progress. In addition, it's been observed that PCIe hotplug events generate Correctable Errors that are handled by hypervisor and then OS. Hypervisor 'borrows' a guest cpu strand briefly to provide the service. If the cpu strand is simultaneously the only cpu targeted by a mondo, it may not be available for the mondo in 20msec, causing SUN4V mondo timeout. It appears that 1 second is the agreed wait time between hypervisor and guest OS, this patch makes the adjustment. Orabug: 25476541 Orabug: 26417466 Signed-off-by: Jane Chu Reviewed-by: Steve Sistare Reviewed-by: Anthony Yznaga Reviewed-by: Rob Gardner Reviewed-by: Thomas Tai Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix gup_huge_pmd

2017-07-21T04:59:06Z

[ Upstream commit dbd2667a4fb9ce4f547982b07cd69dda127c47ea ] The function assumes that each PMD points to head of a huge page. This is not correct as a PMD can point to start of any 8M region with a, say 256M, hugepage. The fix ensures that it points to the correct head of any PMD huge page. Cc: Julian Calaby Signed-off-by: Nitin Gupta Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Adding the type of exported symbols

2017-07-21T04:59:06Z

[ Upstream commit f5a651f1d5e524cab345250a783702fb6a3f14d6 ] Missing symbol type for few functions prevents genksyms from generating symbol versions for those functions. This patch fixes them. Signed-off-by: Nagarathnam Muthusamy Reviewed-by: Babu Moger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sed regex in Makefile.build requires line break between exported symbols

2017-07-21T04:59:06Z

[ Upstream commit d16c0649feb4fe4e814f44803df5a617769c3233 ] The following regex in Makefile.build matches only one ___EXPORT_SYMBOL per line. sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ATOMIC_OPS macro in atomic_64.S expands multiple symbols in same line hence version generation is done only for the last matched symbol. This patch adds new line between the symbol expansions. Signed-off-by: Nagarathnam Muthusamy Reviewed-by: Babu Moger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Adding asm-prototypes.h for genksyms to generate crc

2017-07-21T04:59:06Z

[ Upstream commit bdca8cc096203b17ad0ac4e19f50578207e054d2 ] This patch adds the prototypes of assembly defined functions to asm-prototypes.h. Some prototypes are directly added as they are not present in any existing header files. Signed-off-by: Nagarathnam Muthusamy Reviewed-by: Babu Moger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

arch: remove unused macro/function thread_saved_pc()

2017-06-28T23:13:57Z

The only user of thread_saved_pc() in non-arch-specific code was removed in commit 8243d5597793 ("sched/core: Remove pointless printout in sched_show_task()"). Remove the implementations as well. Some architectures use thread_saved_pc() in their arch-specific code. Leave their thread_saved_pc() intact. Signed-off-by: Tobias Klauser Acked-by: Geert Uytterhoeven Cc: Ingo Molnar Signed-off-by: Linus Torvalds