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84c75286f5
The old ARMv5-style page table format includes a kind of second level descriptor named the "extended small page" format, whose primary purpose is to allow specification of the TEX memory attribute bits on a 4K page. This exists on ARMv6 and also (as an implementation extension) on XScale CPUs; it's UNPREDICTABLE on v5. We were mishandling this in two ways: (1) we weren't implementing it for v6 (probably never noticed because Linux will use the new-style v6 page table format there) (2) we were not correctly setting the page_size, which is 4K, not 1K The latter bug went unnoticed for years because the only thing which the page_size affects is which TLB entries get flushed when the guest does a TLB invalidate on an address in the page, and prior to commit 2f0d8631b7 we were doing a full TLB flush very frequently due to Linux's habit of writing the SCTLR pointlessly a lot. (We can assume that after commit 2f0d8631b7 the bug went unnoticed for a year because nobody's actually using the Zaurus/XScale emulation...) Report the correct page size for these descriptors, and permit them on ARMv6 CPUs. This fixes a problem where a kernel image for Zaurus can boot the kernel OK but gets random segfaults when it tries to run userspace programs. Backports commit fc1891c74ae122a9dc7854f38bae7db03cd911e6 from qemu |
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arm_ldst.h | ||
cpu-qom.h | ||
cpu.c | ||
cpu.h | ||
cpu64.c | ||
crypto_helper.c | ||
helper-a64.c | ||
helper-a64.h | ||
helper.c | ||
helper.h | ||
internals.h | ||
iwmmxt_helper.c | ||
kvm-consts.h | ||
Makefile.objs | ||
neon_helper.c | ||
op_addsub.h | ||
op_helper.c | ||
psci.c | ||
translate-a64.c | ||
translate.c | ||
translate.h | ||
unicorn.h | ||
unicorn_aarch64.c | ||
unicorn_arm.c |