[PATCH v2 04/21] MIPS: genex: Fix except_vec_vi for kernel in XKPHYS

From: Gregory CLEMENT
Date: Thu Nov 23 2023 - 10:27:18 EST


From: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>

Use {highest, higher, hi, lo} immediate loading sequence
to load 64 bit jump address for handler when kernel is
loaded to XKPHYS.

Co-developed-by: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>
Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>
Co-developed-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
---
arch/mips/kernel/genex.S | 19 +++++++++++++++----
arch/mips/kernel/traps.c | 34 ++++++++++++++++++++++++----------
2 files changed, 39 insertions(+), 14 deletions(-)

diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index b6de8e88c1bd4..fd765ad9ecac0 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -272,11 +272,22 @@ NESTED(except_vec_vi, 0, sp)
.set push
.set noreorder
PTR_LA v1, except_vec_vi_handler
-FEXPORT(except_vec_vi_lui)
- lui v0, 0 /* Patched */
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
+FEXPORT(except_vec_vi_hi)
+ lui v0, 0 /* Patched */
+#else
+FEXPORT(except_vec_vi_highest)
+ lui v0, 0 /* Patched */
+FEXPORT(except_vec_vi_higher)
+ daddiu v0, 0 /* Patched */
+ dsll v0, 16
+FEXPORT(except_vec_vi_hi)
+ daddiu v0, 0 /* Patched */
+ dsll v0, 16
+#endif
jr v1
-FEXPORT(except_vec_vi_ori)
- ori v0, 0 /* Patched */
+FEXPORT(except_vec_vi_lo)
+ PTR_ADDIU v0, 0 /* Patched */
.set pop
END(except_vec_vi)
EXPORT(except_vec_vi_end)
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 246c6a6b02614..60c513c51684f 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -2091,18 +2091,26 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
* If no shadow set is selected then use the default handler
* that does normal register saving and standard interrupt exit
*/
- extern const u8 except_vec_vi[], except_vec_vi_lui[];
- extern const u8 except_vec_vi_ori[], except_vec_vi_end[];
+ extern const u8 except_vec_vi[], except_vec_vi_hi[];
+ extern const u8 except_vec_vi_lo[], except_vec_vi_end[];
+#if defined(CONFIG_64BIT) && !defined(KBUILD_64BIT_SYM32)
+ extern const u8 except_vec_vi_highest[], except_vec_vi_higher[];
+#endif
extern const u8 rollback_except_vec_vi[];
const u8 *vec_start = using_rollback_handler() ?
rollback_except_vec_vi : except_vec_vi;
#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
- const int lui_offset = except_vec_vi_lui - vec_start + 2;
- const int ori_offset = except_vec_vi_ori - vec_start + 2;
+ const int imm_offset = 2;
#else
- const int lui_offset = except_vec_vi_lui - vec_start;
- const int ori_offset = except_vec_vi_ori - vec_start;
+ const int imm_offset = 0;
+#endif
+#if defined(CONFIG_64BIT) && !defined(KBUILD_64BIT_SYM32)
+ const int highest_offset = except_vec_vi_highest - vec_start + imm_offset;
+ const int higher_offset = except_vec_vi_higher - vec_start + imm_offset;
#endif
+ const int hi_offset = except_vec_vi_hi - vec_start + imm_offset;
+ const int lo_offset = except_vec_vi_lo - vec_start + imm_offset;
+
const int handler_len = except_vec_vi_end - vec_start;

if (handler_len > VECTORSPACING) {
@@ -2119,10 +2127,16 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
#else
handler_len);
#endif
- h = (u16 *)(b + lui_offset);
- *h = (handler >> 16) & 0xffff;
- h = (u16 *)(b + ori_offset);
- *h = (handler & 0xffff);
+#if defined(CONFIG_64BIT) && !defined(KBUILD_64BIT_SYM32)
+ h = (u16 *)(b + highest_offset);
+ *h = uasm_rel_highest(handler);
+ h = (u16 *)(b + higher_offset);
+ *h = uasm_rel_higher(handler);
+#endif
+ h = (u16 *)(b + hi_offset);
+ *h = uasm_rel_hi(handler);
+ h = (u16 *)(b + lo_offset);
+ *h = uasm_rel_lo(handler);
local_flush_icache_range((unsigned long)b,
(unsigned long)(b+handler_len));
}
--
2.42.0