> -----Original Message-----
> From: Brian Cain <[email protected]>
> Sent: Tuesday, October 7, 2025 7:48 PM
> To: [email protected]
> Cc: [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; Alex Rønne Petersen <[email protected]>;
> Laurent Vivier <[email protected]>
> Subject: [PATCH 1/2] linux-user/hexagon: Fix sigcontext
>
> In order to correspond with the kernel, we've now (1) moved the preds[] to
> the right offset and combined the representation as a single ulong "p3_0",
> (2),
> added the cs{0,1} registers, (3) added a pad for 48 words, (4) added the user
> regs structure to an 8-byte aligned target_sigcontext structure.
Should you include the other control registers also (e.g., framekey)? Perhaps
this is a bug in the kernel as well?
>
> Co-authored-by: Alex Rønne Petersen <[email protected]>
> Signed-off-by: Brian Cain <[email protected]>
> ---
> linux-user/hexagon/signal.c | 199 ++++++++++++++++++++----------------
> 1 file changed, 111 insertions(+), 88 deletions(-)
>
> diff --git a/linux-user/hexagon/signal.c b/linux-user/hexagon/signal.c index
> 492b51f155..6c3dbf91fa 100644
> --- a/linux-user/hexagon/signal.c
> +++ b/linux-user/hexagon/signal.c
> @@ -23,7 +23,7 @@
> #include "signal-common.h"
> #include "linux-user/trace.h"
>
> -struct target_sigcontext {
> +struct target_user_regs_struct {
> target_ulong r0, r1, r2, r3;
> target_ulong r4, r5, r6, r7;
> target_ulong r8, r9, r10, r11;
Consider creating an array for these, then use a for loop below.
> @@ -39,14 +39,21 @@ struct target_sigcontext {
> target_ulong m0;
> target_ulong m1;
> target_ulong usr;
> + target_ulong p3_0;
> target_ulong gp;
> target_ulong ugp;
> target_ulong pc;
> target_ulong cause;
> target_ulong badva;
> - target_ulong pred[NUM_PREGS];
> + target_ulong cs0;
> + target_ulong cs1;
> + target_ulong pad1;
> };
>
> +struct target_sigcontext {
> + struct target_user_regs_struct sc_regs; }
> +__attribute__((aligned(8)));
> +
> struct target_ucontext {
> unsigned long uc_flags;
> target_ulong uc_link; /* target pointer */ @@ -76,53 +83,63 @@ static
> abi_ulong get_sigframe(struct target_sigaction *ka,
>
> static void setup_sigcontext(struct target_sigcontext *sc, CPUHexagonState
> *env) {
> - __put_user(env->gpr[HEX_REG_R00], &sc->r0);
> - __put_user(env->gpr[HEX_REG_R01], &sc->r1);
> - __put_user(env->gpr[HEX_REG_R02], &sc->r2);
> - __put_user(env->gpr[HEX_REG_R03], &sc->r3);
> - __put_user(env->gpr[HEX_REG_R04], &sc->r4);
> - __put_user(env->gpr[HEX_REG_R05], &sc->r5);
> - __put_user(env->gpr[HEX_REG_R06], &sc->r6);
> - __put_user(env->gpr[HEX_REG_R07], &sc->r7);
> - __put_user(env->gpr[HEX_REG_R08], &sc->r8);
> - __put_user(env->gpr[HEX_REG_R09], &sc->r9);
> - __put_user(env->gpr[HEX_REG_R10], &sc->r10);
> - __put_user(env->gpr[HEX_REG_R11], &sc->r11);
> - __put_user(env->gpr[HEX_REG_R12], &sc->r12);
> - __put_user(env->gpr[HEX_REG_R13], &sc->r13);
> - __put_user(env->gpr[HEX_REG_R14], &sc->r14);
> - __put_user(env->gpr[HEX_REG_R15], &sc->r15);
> - __put_user(env->gpr[HEX_REG_R16], &sc->r16);
> - __put_user(env->gpr[HEX_REG_R17], &sc->r17);
> - __put_user(env->gpr[HEX_REG_R18], &sc->r18);
> - __put_user(env->gpr[HEX_REG_R19], &sc->r19);
> - __put_user(env->gpr[HEX_REG_R20], &sc->r20);
> - __put_user(env->gpr[HEX_REG_R21], &sc->r21);
> - __put_user(env->gpr[HEX_REG_R22], &sc->r22);
> - __put_user(env->gpr[HEX_REG_R23], &sc->r23);
> - __put_user(env->gpr[HEX_REG_R24], &sc->r24);
> - __put_user(env->gpr[HEX_REG_R25], &sc->r25);
> - __put_user(env->gpr[HEX_REG_R26], &sc->r26);
> - __put_user(env->gpr[HEX_REG_R27], &sc->r27);
> - __put_user(env->gpr[HEX_REG_R28], &sc->r28);
> - __put_user(env->gpr[HEX_REG_R29], &sc->r29);
> - __put_user(env->gpr[HEX_REG_R30], &sc->r30);
> - __put_user(env->gpr[HEX_REG_R31], &sc->r31);
> - __put_user(env->gpr[HEX_REG_SA0], &sc->sa0);
> - __put_user(env->gpr[HEX_REG_LC0], &sc->lc0);
> - __put_user(env->gpr[HEX_REG_SA1], &sc->sa1);
> - __put_user(env->gpr[HEX_REG_LC1], &sc->lc1);
> - __put_user(env->gpr[HEX_REG_M0], &sc->m0);
> - __put_user(env->gpr[HEX_REG_M1], &sc->m1);
> - __put_user(env->gpr[HEX_REG_USR], &sc->usr);
> - __put_user(env->gpr[HEX_REG_GP], &sc->gp);
> - __put_user(env->gpr[HEX_REG_UGP], &sc->ugp);
> - __put_user(env->gpr[HEX_REG_PC], &sc->pc);
> + __put_user(env->gpr[HEX_REG_R00], &sc->sc_regs.r0);
> + __put_user(env->gpr[HEX_REG_R01], &sc->sc_regs.r1);
> + __put_user(env->gpr[HEX_REG_R02], &sc->sc_regs.r2);
> + __put_user(env->gpr[HEX_REG_R03], &sc->sc_regs.r3);
> + __put_user(env->gpr[HEX_REG_R04], &sc->sc_regs.r4);
> + __put_user(env->gpr[HEX_REG_R05], &sc->sc_regs.r5);
> + __put_user(env->gpr[HEX_REG_R06], &sc->sc_regs.r6);
> + __put_user(env->gpr[HEX_REG_R07], &sc->sc_regs.r7);
> + __put_user(env->gpr[HEX_REG_R08], &sc->sc_regs.r8);
> + __put_user(env->gpr[HEX_REG_R09], &sc->sc_regs.r9);
> + __put_user(env->gpr[HEX_REG_R10], &sc->sc_regs.r10);
> + __put_user(env->gpr[HEX_REG_R11], &sc->sc_regs.r11);
> + __put_user(env->gpr[HEX_REG_R12], &sc->sc_regs.r12);
> + __put_user(env->gpr[HEX_REG_R13], &sc->sc_regs.r13);
> + __put_user(env->gpr[HEX_REG_R14], &sc->sc_regs.r14);
> + __put_user(env->gpr[HEX_REG_R15], &sc->sc_regs.r15);
> + __put_user(env->gpr[HEX_REG_R16], &sc->sc_regs.r16);
> + __put_user(env->gpr[HEX_REG_R17], &sc->sc_regs.r17);
> + __put_user(env->gpr[HEX_REG_R18], &sc->sc_regs.r18);
> + __put_user(env->gpr[HEX_REG_R19], &sc->sc_regs.r19);
> + __put_user(env->gpr[HEX_REG_R20], &sc->sc_regs.r20);
> + __put_user(env->gpr[HEX_REG_R21], &sc->sc_regs.r21);
> + __put_user(env->gpr[HEX_REG_R22], &sc->sc_regs.r22);
> + __put_user(env->gpr[HEX_REG_R23], &sc->sc_regs.r23);
> + __put_user(env->gpr[HEX_REG_R24], &sc->sc_regs.r24);
> + __put_user(env->gpr[HEX_REG_R25], &sc->sc_regs.r25);
> + __put_user(env->gpr[HEX_REG_R26], &sc->sc_regs.r26);
> + __put_user(env->gpr[HEX_REG_R27], &sc->sc_regs.r27);
> + __put_user(env->gpr[HEX_REG_R28], &sc->sc_regs.r28);
> + __put_user(env->gpr[HEX_REG_R29], &sc->sc_regs.r29);
> + __put_user(env->gpr[HEX_REG_R30], &sc->sc_regs.r30);
> + __put_user(env->gpr[HEX_REG_R31], &sc->sc_regs.r31);
Replace the above with a for loop when the GPRs are declared as an array.
> + __put_user(env->gpr[HEX_REG_SA0], &sc->sc_regs.sa0);
> + __put_user(env->gpr[HEX_REG_LC0], &sc->sc_regs.lc0);
> + __put_user(env->gpr[HEX_REG_SA1], &sc->sc_regs.sa1);
> + __put_user(env->gpr[HEX_REG_LC1], &sc->sc_regs.lc1);
> + __put_user(env->gpr[HEX_REG_M0], &sc->sc_regs.m0);
> + __put_user(env->gpr[HEX_REG_M1], &sc->sc_regs.m1);
> + __put_user(env->gpr[HEX_REG_USR], &sc->sc_regs.usr);
> + __put_user(env->gpr[HEX_REG_GP], &sc->sc_regs.gp);
> + __put_user(env->gpr[HEX_REG_UGP], &sc->sc_regs.ugp);
> + __put_user(env->gpr[HEX_REG_PC], &sc->sc_regs.pc);
>
> + /* Consolidate predicates into p3_0 */
> + target_ulong preds = 0;
> int i;
> for (i = 0; i < NUM_PREGS; i++) {
> - __put_user(env->pred[i], &(sc->pred[i]));
> + preds |= (env->pred[i] & 0xff) << (i * 8);
> }
> + __put_user(preds, &sc->sc_regs.p3_0);
> +
> + /* Set cause and badva to 0 - these are set by kernel on exceptions */
> + __put_user(0, &sc->sc_regs.cause);
> + __put_user(0, &sc->sc_regs.badva);
Strange that we have this if they are ignored. Perhaps it's to match the
kernel behavior.
> +
> + __put_user(env->gpr[HEX_REG_CS0], &sc->sc_regs.cs0);
> + __put_user(env->gpr[HEX_REG_CS1], &sc->sc_regs.cs1);
> }
>
> static void setup_ucontext(struct target_ucontext *uc, @@ -192,53 +209,59
> @@ badframe:
> static void restore_sigcontext(CPUHexagonState *env,
> struct target_sigcontext *sc) {
> - __get_user(env->gpr[HEX_REG_R00], &sc->r0);
> - __get_user(env->gpr[HEX_REG_R01], &sc->r1);
> - __get_user(env->gpr[HEX_REG_R02], &sc->r2);
> - __get_user(env->gpr[HEX_REG_R03], &sc->r3);
> - __get_user(env->gpr[HEX_REG_R04], &sc->r4);
> - __get_user(env->gpr[HEX_REG_R05], &sc->r5);
> - __get_user(env->gpr[HEX_REG_R06], &sc->r6);
> - __get_user(env->gpr[HEX_REG_R07], &sc->r7);
> - __get_user(env->gpr[HEX_REG_R08], &sc->r8);
> - __get_user(env->gpr[HEX_REG_R09], &sc->r9);
> - __get_user(env->gpr[HEX_REG_R10], &sc->r10);
> - __get_user(env->gpr[HEX_REG_R11], &sc->r11);
> - __get_user(env->gpr[HEX_REG_R12], &sc->r12);
> - __get_user(env->gpr[HEX_REG_R13], &sc->r13);
> - __get_user(env->gpr[HEX_REG_R14], &sc->r14);
> - __get_user(env->gpr[HEX_REG_R15], &sc->r15);
> - __get_user(env->gpr[HEX_REG_R16], &sc->r16);
> - __get_user(env->gpr[HEX_REG_R17], &sc->r17);
> - __get_user(env->gpr[HEX_REG_R18], &sc->r18);
> - __get_user(env->gpr[HEX_REG_R19], &sc->r19);
> - __get_user(env->gpr[HEX_REG_R20], &sc->r20);
> - __get_user(env->gpr[HEX_REG_R21], &sc->r21);
> - __get_user(env->gpr[HEX_REG_R22], &sc->r22);
> - __get_user(env->gpr[HEX_REG_R23], &sc->r23);
> - __get_user(env->gpr[HEX_REG_R24], &sc->r24);
> - __get_user(env->gpr[HEX_REG_R25], &sc->r25);
> - __get_user(env->gpr[HEX_REG_R26], &sc->r26);
> - __get_user(env->gpr[HEX_REG_R27], &sc->r27);
> - __get_user(env->gpr[HEX_REG_R28], &sc->r28);
> - __get_user(env->gpr[HEX_REG_R29], &sc->r29);
> - __get_user(env->gpr[HEX_REG_R30], &sc->r30);
> - __get_user(env->gpr[HEX_REG_R31], &sc->r31);
> - __get_user(env->gpr[HEX_REG_SA0], &sc->sa0);
> - __get_user(env->gpr[HEX_REG_LC0], &sc->lc0);
> - __get_user(env->gpr[HEX_REG_SA1], &sc->sa1);
> - __get_user(env->gpr[HEX_REG_LC1], &sc->lc1);
> - __get_user(env->gpr[HEX_REG_M0], &sc->m0);
> - __get_user(env->gpr[HEX_REG_M1], &sc->m1);
> - __get_user(env->gpr[HEX_REG_USR], &sc->usr);
> - __get_user(env->gpr[HEX_REG_GP], &sc->gp);
> - __get_user(env->gpr[HEX_REG_UGP], &sc->ugp);
> - __get_user(env->gpr[HEX_REG_PC], &sc->pc);
> + __get_user(env->gpr[HEX_REG_R00], &sc->sc_regs.r0);
> + __get_user(env->gpr[HEX_REG_R01], &sc->sc_regs.r1);
> + __get_user(env->gpr[HEX_REG_R02], &sc->sc_regs.r2);
> + __get_user(env->gpr[HEX_REG_R03], &sc->sc_regs.r3);
> + __get_user(env->gpr[HEX_REG_R04], &sc->sc_regs.r4);
> + __get_user(env->gpr[HEX_REG_R05], &sc->sc_regs.r5);
> + __get_user(env->gpr[HEX_REG_R06], &sc->sc_regs.r6);
> + __get_user(env->gpr[HEX_REG_R07], &sc->sc_regs.r7);
> + __get_user(env->gpr[HEX_REG_R08], &sc->sc_regs.r8);
> + __get_user(env->gpr[HEX_REG_R09], &sc->sc_regs.r9);
> + __get_user(env->gpr[HEX_REG_R10], &sc->sc_regs.r10);
> + __get_user(env->gpr[HEX_REG_R11], &sc->sc_regs.r11);
> + __get_user(env->gpr[HEX_REG_R12], &sc->sc_regs.r12);
> + __get_user(env->gpr[HEX_REG_R13], &sc->sc_regs.r13);
> + __get_user(env->gpr[HEX_REG_R14], &sc->sc_regs.r14);
> + __get_user(env->gpr[HEX_REG_R15], &sc->sc_regs.r15);
> + __get_user(env->gpr[HEX_REG_R16], &sc->sc_regs.r16);
> + __get_user(env->gpr[HEX_REG_R17], &sc->sc_regs.r17);
> + __get_user(env->gpr[HEX_REG_R18], &sc->sc_regs.r18);
> + __get_user(env->gpr[HEX_REG_R19], &sc->sc_regs.r19);
> + __get_user(env->gpr[HEX_REG_R20], &sc->sc_regs.r20);
> + __get_user(env->gpr[HEX_REG_R21], &sc->sc_regs.r21);
> + __get_user(env->gpr[HEX_REG_R22], &sc->sc_regs.r22);
> + __get_user(env->gpr[HEX_REG_R23], &sc->sc_regs.r23);
> + __get_user(env->gpr[HEX_REG_R24], &sc->sc_regs.r24);
> + __get_user(env->gpr[HEX_REG_R25], &sc->sc_regs.r25);
> + __get_user(env->gpr[HEX_REG_R26], &sc->sc_regs.r26);
> + __get_user(env->gpr[HEX_REG_R27], &sc->sc_regs.r27);
> + __get_user(env->gpr[HEX_REG_R28], &sc->sc_regs.r28);
> + __get_user(env->gpr[HEX_REG_R29], &sc->sc_regs.r29);
> + __get_user(env->gpr[HEX_REG_R30], &sc->sc_regs.r30);
> + __get_user(env->gpr[HEX_REG_R31], &sc->sc_regs.r31);
Replace the above with a for loop when the GPRs are declared as an array.
> + __get_user(env->gpr[HEX_REG_SA0], &sc->sc_regs.sa0);
> + __get_user(env->gpr[HEX_REG_LC0], &sc->sc_regs.lc0);
> + __get_user(env->gpr[HEX_REG_SA1], &sc->sc_regs.sa1);
> + __get_user(env->gpr[HEX_REG_LC1], &sc->sc_regs.lc1);
> + __get_user(env->gpr[HEX_REG_M0], &sc->sc_regs.m0);
> + __get_user(env->gpr[HEX_REG_M1], &sc->sc_regs.m1);
> + __get_user(env->gpr[HEX_REG_USR], &sc->sc_regs.usr);
> + __get_user(env->gpr[HEX_REG_GP], &sc->sc_regs.gp);
> + __get_user(env->gpr[HEX_REG_UGP], &sc->sc_regs.ugp);
> + __get_user(env->gpr[HEX_REG_PC], &sc->sc_regs.pc);
>
> + /* Restore predicates from p3_0 */
> + target_ulong preds;
> + __get_user(preds, &sc->sc_regs.p3_0);
> int i;
> for (i = 0; i < NUM_PREGS; i++) {
> - __get_user(env->pred[i], &(sc->pred[i]));
> + env->pred[i] = (preds >> (i * 8)) & 0xff;
> }
> +
> + __get_user(env->gpr[HEX_REG_CS0], &sc->sc_regs.cs0);
> + __get_user(env->gpr[HEX_REG_CS1], &sc->sc_regs.cs1);
> }
>
> static void restore_ucontext(CPUHexagonState *env, struct target_ucontext
> *uc)
> --
> 2.34.1
