xemu/target
Peter Maydell 7cba3a05b5 target/arm: Explicitly select short-format FSR for M-profile
For M-profile, there is no guest-facing A-profile format FSR, but we
still use the env->exception.fsr field to pass fault information from
the point where a fault is raised to the code in
arm_v7m_cpu_do_interrupt() which interprets it and sets the M-profile
specific fault status registers.  So it doesn't matter whether we
fill in env->exception.fsr in the short format or the LPAE format, as
long as both sides agree.  As it happens arm_v7m_cpu_do_interrupt()
assumes short-form.

In compute_fsr_fsc() we weren't explicitly choosing short-form for
M-profile, but instead relied on it falling out in the wash because
arm_s1_regime_using_lpae_format() would be false.  This was broken in
commit 452c67a4 when we added v8R support, because we said "PMSAv8 is
always LPAE format" (as it is for v8R), forgetting that we were
implicitly using this code path on M-profile. At that point we would
hit a g_assert_not_reached():
 ERROR:../../target/arm/internals.h:549:arm_fi_to_lfsc: code should not be reached

#7  0x0000555555e055f7 in arm_fi_to_lfsc (fi=0x7fffecff9a90) at ../../target/arm/internals.h:549
#8  0x0000555555e05a27 in compute_fsr_fsc (env=0x555557356670, fi=0x7fffecff9a90, target_el=1, mmu_idx=1, ret_fsc=0x7fffecff9a1c)
    at ../../target/arm/tlb_helper.c:95
#9  0x0000555555e05b62 in arm_deliver_fault (cpu=0x555557354800, addr=268961344, access_type=MMU_INST_FETCH, mmu_idx=1, fi=0x7fffecff9a90)
    at ../../target/arm/tlb_helper.c:132
#10 0x0000555555e06095 in arm_cpu_tlb_fill (cs=0x555557354800, address=268961344, size=1, access_type=MMU_INST_FETCH, mmu_idx=1, probe=false, retaddr=0)
    at ../../target/arm/tlb_helper.c:260

The specific assertion changed when commit fcc7404eff24b4c added
"assert not M-profile" to arm_is_secure_below_el3(), because the
conditions being checked in compute_fsr_fsc() include
arm_el_is_aa64(), which will end up calling arm_is_secure_below_el3()
and asserting before we try to call arm_fi_to_lfsc():

#7  0x0000555555efaf43 in arm_is_secure_below_el3 (env=0x5555574665a0) at ../../target/arm/cpu.h:2396
#8  0x0000555555efb103 in arm_is_el2_enabled (env=0x5555574665a0) at ../../target/arm/cpu.h:2448
#9  0x0000555555efb204 in arm_el_is_aa64 (env=0x5555574665a0, el=1) at ../../target/arm/cpu.h:2509
#10 0x0000555555efbdfd in compute_fsr_fsc (env=0x5555574665a0, fi=0x7fffecff99e0, target_el=1, mmu_idx=1, ret_fsc=0x7fffecff996c)

Avoid the assertion and the incorrect FSR format selection by
explicitly making M-profile use the short-format in this function.

Fixes: 452c67a42704 ("target/arm: Enable TTBCR_EAE for ARMv8-R AArch32")a
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1658
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230523131726.866635-1-peter.maydell@linaro.org
(cherry picked from commit d7fe699be54b2cbb8e4ee37b63588b3458a49da7)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2023-05-31 09:43:56 +03:00
..
alpha accel/tcg: Remove will_exit argument from cpu_restore_state 2022-11-01 08:31:41 +11:00
arm target/arm: Explicitly select short-format FSR for M-profile 2023-05-31 09:43:56 +03:00
avr target/avr: Convert to tcg_ops restore_state_to_opc 2022-10-26 11:11:28 +10:00
cris accel/tcg: Remove will_exit argument from cpu_restore_state 2022-11-01 08:31:41 +11:00
hexagon target/hexagon: Convert to tcg_ops restore_state_to_opc 2022-10-26 11:11:28 +10:00
hppa target/hppa: Convert to tcg_ops restore_state_to_opc 2022-10-26 11:11:28 +10:00
i386 target/i386: fix avx2 instructions vzeroall and vpermdq 2023-05-18 21:10:00 +03:00
loongarch target/loongarch: Fix return value of CHECK_FPE 2022-11-07 10:54:11 +08:00
m68k target/m68k: Rename qregs.def -> qregs.h.inc 2022-11-05 20:35:45 +01:00
microblaze accel/tcg: Remove will_exit argument from cpu_restore_state 2022-11-01 08:31:41 +11:00
mips target/mips: Don't check COP1X for 64 bit FP mode 2022-11-08 01:04:25 +01:00
nios2 accel/tcg: Remove will_exit argument from cpu_restore_state 2022-11-01 08:31:41 +11:00
openrisc accel/tcg: Remove will_exit argument from cpu_restore_state 2022-11-01 08:31:41 +11:00
ppc target/ppc: Fix helper_pminsn() prototype 2023-05-18 21:09:59 +03:00
riscv target/riscv: Fix itrigger when icount is used 2023-05-18 21:09:59 +03:00
rx Revert incorrect cflags initialization. 2022-10-26 10:53:41 -04:00
s390x s390x/tcg: Fix LDER instruction format 2023-05-18 21:09:59 +03:00
sh4 target/sh4: Mask restore of env->flags from tb->flags 2023-03-29 10:20:04 +03:00
sparc target/sparc: Convert to tcg_ops restore_state_to_opc 2022-10-26 11:11:28 +10:00
tricore target/tricore: Rename csfr.def -> csfr.h.inc 2022-11-05 20:35:45 +01:00
xtensa accel/tcg: Remove will_exit argument from cpu_restore_state 2022-11-01 08:31:41 +11:00
Kconfig hw/loongarch: Add support loongson3 virt machine type. 2022-06-06 18:09:03 +00:00
meson.build target/loongarch: Add target build suport 2022-06-06 18:09:03 +00:00