Paul Burton 1031398035 MIPS: Mask out limit field when calculating wired entry count ... Since MIPSr6 the Wired register is split into 2 fields, with the upper 16 bits of the register indicating a limit on the value that the wired entry count in the bottom 16 bits of the register can take. This means that simply reading the wired register doesn't get us a valid TLB entry index any longer, and we instead need to retrieve only the lower 16 bits of the register. Introduce a new num_wired_entries() function which does this on MIPSr6 or higher and simply returns the value of the wired register on older architecture revisions, and make use of it when reading the number of wired entries. Since commit e710d66683 ("MIPS: tlb-r4k: If there are wired entries, don't use TLBINVF") we have been using a non-zero number of wired entries to determine whether we should avoid use of the tlbinvf instruction (which would invalidate wired entries) and instead loop over TLB entries in local_flush_tlb_all(). This loop begins with the number of wired entries, or before this patch some large bogus TLB index on MIPSr6 systems. Thus since the aforementioned commit some MIPSr6 systems with FTLBs have been prone to leaving stale address translations in the FTLB & crashing in various weird & wonderful ways when we later observe the wrong memory. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Matt Redfearn <matt.redfearn@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14557/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>		2016-11-24 16:44:16 +01:00
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asm	MIPS: Mask out limit field when calculating wired entry count	2016-11-24 16:44:16 +01:00
uapi/asm	MIPS: Wire up new pkey_{mprotect,alloc,free} syscalls	2016-10-14 11:05:13 -07:00