Replace __siginfo_t with target_pt_regs, and move si_mask
into target_signal_frame directly.
Extract save/restore functions for target_pt_regs. Adjust
for sparc64 tstate. Use proper get/put functions for psr.
Turns out we were already writing to si_mask twice, so no
need to handle that in the new functions.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210426025334.1168495-16-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Correctly implement save/restore of the tstate field in
sparc64_get_context() and sparc64_set_context():
* Don't use the CWP value from the guest in set_context
* Construct and save a tstate value rather than leaving
it as zero in get_context
To do this we factor out the "calculate TSTATE value from CPU state"
code from sparc_cpu_do_interrupt() into its own sparc64_tstate()
function; that in turn requires us to move some of the function
prototypes out from inside a CPU_NO_IO_DEFS ifdef guard.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-5-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Unlike the kernel macros, our __get_user() and __put_user() do not
return a failure code. Kernel code typically has a style of
err |= __get_user(...); err |= __get_user(...);
and then checking err at the end. In sparc64_get_context() our
version of the code dropped the accumulating into err but left the
"if (err) goto do_sigsegv" checks, which will never be taken. Delete
unnecessary if()s.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-3-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The handling of the FPU state in sparc64_get_context() and
sparc64_set_context() is not the same as what the kernel actually
does: we unconditionally read and write the FP registers and the
FSR, GSR and FPRS, but the kernel logic is more complicated:
* in get_context the kernel has code for saving FPU registers,
but it is hidden inside an "if (fenab) condition and the
fenab flag is always set to 0 (inside an "#if 1" which has
been in the kernel for over 15 years). So the effect is that
the FPU state part is always written as zeroes.
* in set_context the kernel looks at the fenab field in the
structure from the guest, and only restores the state if
it is set; it also looks at the structure's FPRS to see
whether either the upper or lower or both halves of the
register file have valid data.
Bring our implementations into line with the kernel:
* in get_context:
- clear the entire target_ucontext at the top of the
function (as the kernel does)
- then don't write the FPU state, so those fields remain zero
- this fixes Coverity issue CID 1432305 by deleting the code
it was complaining about
* in set_context:
- check the fenab and the fpsr to decide which parts of
the FPU data to restore, if any
- instead of setting the FPU registers by doing two
32-bit loads and filling in the .upper and .lower parts
of the CPU_Double union separately, just do a 64-bit
load of the whole register at once. This fixes Coverity
issue CID 1432303 because we now access the dregs[] part
of the mcfpu_fregs union rather than the sregs[] part
(which is not large enough to actually cover the whole of
the data, so we were accessing off the end of sregs[])
We change both functions in a single commit to avoid potentially
breaking bisection.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-2-peter.maydell@linaro.org>
[lv: fix FPRS_DU loop s/31/32/]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.
Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201023122455.19417-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Some platforms used the wrong definition of stack_t where the flags and
size fields were swapped or where the flags field had type ulong instead
of int.
Due to the presence of padding space in the structure and the prevalence
of little-endian machines this problem went unnoticed for a long time.
The type definitions have been cross-checked with the ones defined in
the Linux kernel v5.9, plus some older versions for a few architecture
that have been removed and Xilinx's kernel fork for NiosII [1].
The bsd-user headers remain unchanged as I don't know if they are wrong
or not.
[1] https://github.com/Xilinx/linux-xlnx/blob/master/arch/nios2/include/uapi/asm/signal.h
Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <e9d47692-ee92-009f-6007-0abc3f502b97@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The function do_sigreturn() tries to store the PC, NPC and PSR in
uint32_t local variables, which implicitly drops the high half of
these fields for 64-bit guests.
The usual effect was that a guest which used signals would crash on
return from a signal unless it was lucky enough to take it while the
PC was in the low 4GB of the address space. In particular, Debian
/bin/dash and /bin/bash would segfault after executing external
commands.
Use abi_ulong, which is the type these fields all have in the
__siginfo_t struct.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201105212314.9628-4-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Because QEMU's user-mode emulation just directly accesses guest CPU
state, for SPARC the guest register window state is not the same in
the sparc64_get_context() and sparc64_set_context() functions as it
is for the real kernel's versions of those functions. Specifically,
for the kernel it has saved the user space state such that the O*
registers go into a pt_regs struct as UREG_I*, and the I* registers
have been spilled onto the userspace stack. For QEMU, we haven't
done that, so the guest's O* registers are still in WREG_O* and the
I* registers in WREG_I*.
The code was already accessing the O* registers correctly for QEMU,
but had copied the kernel code for accessing the I* registers off the
userspace stack. Replace this with direct accesses to fp and i7 in
the CPU state, and add a comment explaining why we differ from the
kernel code here.
This fix is sufficient to get bash to a shell prompt.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201105212314.9628-3-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
