diff options
| author | Richard Henderson <rth@twiddle.net> | 2017-07-18 10:02:33 -1000 |
|---|---|---|
| committer | Aurelien Jarno <aurelien@aurel32.net> | 2017-07-18 23:39:16 +0200 |
| commit | b0e4f0edf575f72d8d76717ecbefa9c748ab467b (patch) | |
| tree | 1f77bfb4b132ee85a7e875da73c27174713cbbb4 /linux-user/signal.c | |
| parent | d6a6cffdd3d861c2cdd09253369bba50f9e3d891 (diff) | |
| download | qemu-b0e4f0edf575f72d8d76717ecbefa9c748ab467b.zip | |
linux-user/sh4: Notice gUSA regions during signal delivery
We translate gUSA regions atomically in a parallel context.
But in a serial context a gUSA region may be interrupted.
In that case, restart the region as the kernel would.
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170718200255.31647-9-rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Diffstat (limited to 'linux-user/signal.c')
| -rw-r--r-- | linux-user/signal.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/linux-user/signal.c b/linux-user/signal.c index 3d18d1b3ee..c8b0733a7c 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -3471,6 +3471,30 @@ static abi_ulong get_sigframe(struct target_sigaction *ka, return (sp - frame_size) & -8ul; } +/* Notice when we're in the middle of a gUSA region and reset. + Note that this will only occur for !parallel_cpus, as we will + translate such sequences differently in a parallel context. */ +static void unwind_gusa(CPUSH4State *regs) +{ + /* If the stack pointer is sufficiently negative, and we haven't + completed the sequence, then reset to the entry to the region. */ + /* ??? The SH4 kernel checks for and address above 0xC0000000. + However, the page mappings in qemu linux-user aren't as restricted + and we wind up with the normal stack mapped above 0xF0000000. + That said, there is no reason why the kernel should be allowing + a gUSA region that spans 1GB. Use a tighter check here, for what + can actually be enabled by the immediate move. */ + if (regs->gregs[15] >= -128u && regs->pc < regs->gregs[0]) { + /* Reset the PC to before the gUSA region, as computed from + R0 = region end, SP = -(region size), plus one more for the + insn that actually initializes SP to the region size. */ + regs->pc = regs->gregs[0] + regs->gregs[15] - 2; + + /* Reset the SP to the saved version in R1. */ + regs->gregs[15] = regs->gregs[1]; + } +} + static void setup_sigcontext(struct target_sigcontext *sc, CPUSH4State *regs, unsigned long mask) { @@ -3534,6 +3558,8 @@ static void setup_frame(int sig, struct target_sigaction *ka, abi_ulong frame_addr; int i; + unwind_gusa(regs); + frame_addr = get_sigframe(ka, regs->gregs[15], sizeof(*frame)); trace_user_setup_frame(regs, frame_addr); if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { @@ -3583,6 +3609,8 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka, abi_ulong frame_addr; int i; + unwind_gusa(regs); + frame_addr = get_sigframe(ka, regs->gregs[15], sizeof(*frame)); trace_user_setup_rt_frame(regs, frame_addr); if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { |