diff options
| author | Helge Deller <deller@gmx.de> | 2022-02-18 09:25:20 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-02 11:41:01 +0100 |
| commit | b783ef3eb66a69e0c779fab4696582fb6cfb4a69 (patch) | |
| tree | cf6c3b1e7c1255a233282701aded86590fb7a6c6 /arch/parisc | |
| parent | 0b608b3392c4b3a1d6e9fdc09f99ec6a3402ad36 (diff) | |
parisc/unaligned: Fix fldd and fstd unaligned handlers on 32-bit kernel
commit dd2288f4a020d693360e3e8d72f8b9d9c25f5ef6 upstream.
Usually the kernel provides fixup routines to emulate the fldd and fstd
floating-point instructions if they load or store 8-byte from/to a not
natuarally aligned memory location.
On a 32-bit kernel I noticed that those unaligned handlers didn't worked and
instead the application got a SEGV.
While checking the code I found two problems:
First, the OPCODE_FLDD_L and OPCODE_FSTD_L cases were ifdef'ed out by the
CONFIG_PA20 option, and as such those weren't built on a pure 32-bit kernel.
This is now fixed by moving the CONFIG_PA20 #ifdef to prevent the compilation
of OPCODE_LDD_L and OPCODE_FSTD_L only, and handling the fldd and fstd
instructions.
The second problem are two bugs in the 32-bit inline assembly code, where the
wrong registers where used. The calculation of the natural alignment used %2
(vall) instead of %3 (ior), and the first word was stored back to address %1
(valh) instead of %3 (ior).
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/parisc')
| -rw-r--r-- | arch/parisc/kernel/unaligned.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/parisc/kernel/unaligned.c b/arch/parisc/kernel/unaligned.c index 237d20dd5622..a238b7fe8908 100644 --- a/arch/parisc/kernel/unaligned.c +++ b/arch/parisc/kernel/unaligned.c @@ -397,7 +397,7 @@ static int emulate_std(struct pt_regs *regs, int frreg, int flop) __asm__ __volatile__ ( " mtsp %4, %%sr1\n" " zdep %2, 29, 2, %%r19\n" -" dep %%r0, 31, 2, %2\n" +" dep %%r0, 31, 2, %3\n" " mtsar %%r19\n" " zvdepi -2, 32, %%r19\n" "1: ldw 0(%%sr1,%3),%%r20\n" @@ -409,7 +409,7 @@ static int emulate_std(struct pt_regs *regs, int frreg, int flop) " andcm %%r21, %%r19, %%r21\n" " or %1, %%r20, %1\n" " or %2, %%r21, %2\n" -"3: stw %1,0(%%sr1,%1)\n" +"3: stw %1,0(%%sr1,%3)\n" "4: stw %%r1,4(%%sr1,%3)\n" "5: stw %2,8(%%sr1,%3)\n" " copy %%r0, %0\n" @@ -596,7 +596,6 @@ void handle_unaligned(struct pt_regs *regs) ret = ERR_NOTHANDLED; /* "undefined", but lets kill them. */ break; } -#ifdef CONFIG_PA20 switch (regs->iir & OPCODE2_MASK) { case OPCODE_FLDD_L: @@ -607,14 +606,15 @@ void handle_unaligned(struct pt_regs *regs) flop=1; ret = emulate_std(regs, R2(regs->iir),1); break; +#ifdef CONFIG_PA20 case OPCODE_LDD_L: ret = emulate_ldd(regs, R2(regs->iir),0); break; case OPCODE_STD_L: ret = emulate_std(regs, R2(regs->iir),0); break; - } #endif + } switch (regs->iir & OPCODE3_MASK) { case OPCODE_FLDW_L: |