diff options
| author | Helge Deller <deller@gmx.de> | 2024-09-03 17:22:10 +0200 |
|---|---|---|
| committer | Michael Tokarev <mjt@tls.msk.ru> | 2024-09-05 23:00:34 +0300 |
| commit | e98b0c7b29abb9b85c1081fa2ce5c214d5bc12eb (patch) | |
| tree | 66c863167fe6667e6ddbe8f0a5d61a16fc40c209 | |
| parent | d73ca551a0c0b16413efe531c978c638d12eb783 (diff) | |
target/hppa: Fix PSW V-bit packaging in cpu_hppa_get for hppa64
While adding hppa64 support, the psw_v variable got extended from 32 to 64
bits. So, when packaging the PSW-V bit from the psw_v variable for interrupt
processing, check bit 31 instead the 63th (sign) bit.
This fixes a hard to find Linux kernel boot issue where the loss of the PSW-V
bit due to an ITLB interruption in the middle of a series of ds/addc
instructions (from the divU milicode library) generated the wrong division
result and thus triggered a Linux kernel crash.
Link: https://lore.kernel.org/lkml/718b8afe-222f-4b3a-96d3-93af0e4ceff1@roeck-us.net/
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 931adff31478 ("target/hppa: Update cpu_hppa_get/put_psw for hppa64")
Cc: qemu-stable@nongnu.org # v8.2+
(cherry picked from commit ead5078cf1a5f11d16e3e8462154c859620bcc7e)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(Mjt: context fixup in target/hppa/helper.c due to lack of
v9.0.0-688-gebc9401a4067 "target/hppa: Split PSW X and B into their own field")
| -rw-r--r-- | target/hppa/cpu.h | 2 | ||||
| -rw-r--r-- | target/hppa/helper.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/target/hppa/cpu.h b/target/hppa/cpu.h index 9556e95fab..e29e69dc31 100644 --- a/target/hppa/cpu.h +++ b/target/hppa/cpu.h @@ -188,7 +188,7 @@ typedef struct CPUArchState { target_ulong psw; /* All psw bits except the following: */ target_ulong psw_n; /* boolean */ - target_long psw_v; /* in most significant bit */ + target_long psw_v; /* in bit 31 */ /* Splitting the carry-borrow field into the MSB and "the rest", allows * for "the rest" to be deleted when it is unused, but the MSB is in use. diff --git a/target/hppa/helper.c b/target/hppa/helper.c index 859644c47a..9e35b65f29 100644 --- a/target/hppa/helper.c +++ b/target/hppa/helper.c @@ -53,7 +53,7 @@ target_ulong cpu_hppa_get_psw(CPUHPPAState *env) } psw |= env->psw_n * PSW_N; - psw |= (env->psw_v < 0) * PSW_V; + psw |= ((env->psw_v >> 31) & 1) * PSW_V; psw |= env->psw; return psw; |