From: Lad Prabhakar <[email protected]>
We need to probe for IOCP only once during boot stage, as we were probing
for IOCP for all the stages this caused the below issue during module-init
stage,
[9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
[9.027153] Oops [#1]
[9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
[9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
[9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
[9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
[9.055558] ra : andes_errata_patch_func+0x4a/0x52
[9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
[9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
[9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
[9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
[9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
[9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
[9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
[9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
[9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
[9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
[9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
[9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
[9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
[9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
[9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
[9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
[9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
[9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
[9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
[9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
[9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
[9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
[9.205994] ---[ end trace 0000000000000000 ]---
This is because we called riscv_noncoherent_supported() for all the stages
during IOCP probe. riscv_noncoherent_supported() function sets
noncoherent_supported variable to true which has an annotation set to
"__ro_after_init" due to which we were seeing the above splat. Fix this by
probing for IOCP only once in boot stage by having a boolean variable
is_iocp_probe_done which will be set to true upon IOCP probe in
errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
While at it make return type of errata_probe_iocp() to void as we were
not checking the return value in andes_errata_patch_func().
Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
Signed-off-by: Lad Prabhakar <[email protected]>
---
v1->v2
* As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
variable to probe for IOCP only once.
* Updated commit message
* Make return value of errata_probe_iocp() to void
---
arch/riscv/errata/andes/errata.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
diff --git a/arch/riscv/errata/andes/errata.c b/arch/riscv/errata/andes/errata.c
index 197db68cc8da..b8eadb3b10d8 100644
--- a/arch/riscv/errata/andes/errata.c
+++ b/arch/riscv/errata/andes/errata.c
@@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
return ret.error ? 0 : ret.value;
}
-static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
+static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
{
+ static bool is_iocp_probe_done;
+
if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
- return false;
+ return;
+
+ if (is_iocp_probe_done)
+ return;
if (arch_id != ANDESTECH_AX45MP_MARCHID || impid != ANDESTECH_AX45MP_MIMPID)
- return false;
+ return;
- if (!ax45mp_iocp_sw_workaround())
- return false;
+ if (!ax45mp_iocp_sw_workaround()) {
+ is_iocp_probe_done = true;
+ return;
+ }
/* Set this just to make core cbo code happy */
riscv_cbom_block_size = 1;
riscv_noncoherent_supported();
-
- return true;
+ is_iocp_probe_done = true;
}
void __init_or_module andes_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
unsigned long archid, unsigned long impid,
unsigned int stage)
{
- errata_probe_iocp(stage, archid, impid);
+ if (stage == RISCV_ALTERNATIVES_BOOT)
+ errata_probe_iocp(stage, archid, impid);
/* we have nothing to patch here ATM so just return back */
}
--
2.34.1
Hi Prabhakar,
On Thu, Nov 30, 2023 at 1:56 PM Prabhakar <[email protected]> wrote:
> From: Lad Prabhakar <[email protected]>
>
> We need to probe for IOCP only once during boot stage, as we were probing
> for IOCP for all the stages this caused the below issue during module-init
> stage,
>
> [9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
> [9.027153] Oops [#1]
> [9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
> [9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
> [9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> [9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
> [9.055558] ra : andes_errata_patch_func+0x4a/0x52
> [9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
> [9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
> [9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
> [9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
> [9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
> [9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
> [9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
> [9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
> [9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
> [9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
> [9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
> [9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
> [9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
> [9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
> [9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
> [9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
> [9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
> [9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
> [9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
> [9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
> [9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
> [9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
> [9.205994] ---[ end trace 0000000000000000 ]---
>
> This is because we called riscv_noncoherent_supported() for all the stages
> during IOCP probe. riscv_noncoherent_supported() function sets
> noncoherent_supported variable to true which has an annotation set to
> "__ro_after_init" due to which we were seeing the above splat. Fix this by
> probing for IOCP only once in boot stage by having a boolean variable
> is_iocp_probe_done which will be set to true upon IOCP probe in
> errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
>
> While at it make return type of errata_probe_iocp() to void as we were
> not checking the return value in andes_errata_patch_func().
>
> Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
> Signed-off-by: Lad Prabhakar <[email protected]>
> ---
> v1->v2
> * As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
> variable to probe for IOCP only once.
> * Updated commit message
> * Make return value of errata_probe_iocp() to void
Thanks for the update!
> --- a/arch/riscv/errata/andes/errata.c
> +++ b/arch/riscv/errata/andes/errata.c
> @@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
> return ret.error ? 0 : ret.value;
> }
>
> -static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> +static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> {
> + static bool is_iocp_probe_done;
done?
> +
> if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> - return false;
> + return;
> +
> + if (is_iocp_probe_done)
> + return;
>
Why not keep it simple, and just do
done = true;
here?
Can arch_id or impid suddenly change, so you have to recheck?
If the SBI call in ax45mp_iocp_sw_workaround() fails, is there really
a need to try it again later?
> if (arch_id != ANDESTECH_AX45MP_MARCHID || impid != ANDESTECH_AX45MP_MIMPID)
> - return false;
> + return;
>
> - if (!ax45mp_iocp_sw_workaround())
> - return false;
> + if (!ax45mp_iocp_sw_workaround()) {
> + is_iocp_probe_done = true;
> + return;
> + }
>
> /* Set this just to make core cbo code happy */
> riscv_cbom_block_size = 1;
> riscv_noncoherent_supported();
> -
> - return true;
> + is_iocp_probe_done = true;
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
Hi Geert,
Thank you for the review.
On Thu, Nov 30, 2023 at 2:34 PM Geert Uytterhoeven <[email protected]> wrote:
>
> Hi Prabhakar,
>
> On Thu, Nov 30, 2023 at 1:56 PM Prabhakar <[email protected]> wrote:
> > From: Lad Prabhakar <[email protected]>
> >
> > We need to probe for IOCP only once during boot stage, as we were probing
> > for IOCP for all the stages this caused the below issue during module-init
> > stage,
> >
> > [9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
> > [9.027153] Oops [#1]
> > [9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
> > [9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
> > [9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> > [9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
> > [9.055558] ra : andes_errata_patch_func+0x4a/0x52
> > [9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
> > [9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
> > [9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
> > [9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
> > [9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
> > [9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
> > [9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
> > [9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
> > [9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
> > [9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
> > [9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
> > [9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
> > [9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
> > [9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
> > [9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
> > [9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
> > [9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
> > [9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
> > [9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
> > [9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
> > [9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
> > [9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
> > [9.205994] ---[ end trace 0000000000000000 ]---
> >
> > This is because we called riscv_noncoherent_supported() for all the stages
> > during IOCP probe. riscv_noncoherent_supported() function sets
> > noncoherent_supported variable to true which has an annotation set to
> > "__ro_after_init" due to which we were seeing the above splat. Fix this by
> > probing for IOCP only once in boot stage by having a boolean variable
> > is_iocp_probe_done which will be set to true upon IOCP probe in
> > errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
> >
> > While at it make return type of errata_probe_iocp() to void as we were
> > not checking the return value in andes_errata_patch_func().
> >
> > Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
> > Signed-off-by: Lad Prabhakar <[email protected]>
> > ---
> > v1->v2
> > * As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
> > variable to probe for IOCP only once.
> > * Updated commit message
> > * Make return value of errata_probe_iocp() to void
>
> Thanks for the update!
>
> > --- a/arch/riscv/errata/andes/errata.c
> > +++ b/arch/riscv/errata/andes/errata.c
> > @@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
> > return ret.error ? 0 : ret.value;
> > }
> >
> > -static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > +static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > {
> > + static bool is_iocp_probe_done;
>
> done?
>
OK I'll rename it to "done".
> > +
> > if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> > - return false;
> > + return;
> > +
> > + if (is_iocp_probe_done)
> > + return;
> >
>
> Why not keep it simple, and just do
>
> done = true;
>
OK.
> here?
> Can arch_id or impid suddenly change, so you have to recheck?
I only check arch_id and impid here. Are you suggesting I drop it?
> If the SBI call in ax45mp_iocp_sw_workaround() fails, is there really
> a need to try it again later?
>
No if it fails we just continue with a broken system.
Cheers,
Prabhakar
> > if (arch_id != ANDESTECH_AX45MP_MARCHID || impid != ANDESTECH_AX45MP_MIMPID)
> > - return false;
> > + return;
> >
> > - if (!ax45mp_iocp_sw_workaround())
> > - return false;
> > + if (!ax45mp_iocp_sw_workaround()) {
> > + is_iocp_probe_done = true;
> > + return;
> > + }
> >
> > /* Set this just to make core cbo code happy */
> > riscv_cbom_block_size = 1;
> > riscv_noncoherent_supported();
> > -
> > - return true;
> > + is_iocp_probe_done = true;
> > }
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds
Hi Prabhakar,
On Thu, Nov 30, 2023 at 5:23 PM Lad, Prabhakar
<[email protected]> wrote:
> On Thu, Nov 30, 2023 at 2:34 PM Geert Uytterhoeven <[email protected]> wrote:
> > On Thu, Nov 30, 2023 at 1:56 PM Prabhakar <[email protected]> wrote:
> > > From: Lad Prabhakar <[email protected]>
> > >
> > > We need to probe for IOCP only once during boot stage, as we were probing
> > > for IOCP for all the stages this caused the below issue during module-init
> > > stage,
> > >
> > > [9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
> > > [9.027153] Oops [#1]
> > > [9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
> > > [9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
> > > [9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> > > [9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
> > > [9.055558] ra : andes_errata_patch_func+0x4a/0x52
> > > [9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
> > > [9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
> > > [9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
> > > [9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
> > > [9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
> > > [9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
> > > [9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
> > > [9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
> > > [9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
> > > [9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
> > > [9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
> > > [9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
> > > [9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
> > > [9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
> > > [9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
> > > [9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
> > > [9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
> > > [9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
> > > [9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
> > > [9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
> > > [9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
> > > [9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
> > > [9.205994] ---[ end trace 0000000000000000 ]---
> > >
> > > This is because we called riscv_noncoherent_supported() for all the stages
> > > during IOCP probe. riscv_noncoherent_supported() function sets
> > > noncoherent_supported variable to true which has an annotation set to
> > > "__ro_after_init" due to which we were seeing the above splat. Fix this by
> > > probing for IOCP only once in boot stage by having a boolean variable
> > > is_iocp_probe_done which will be set to true upon IOCP probe in
> > > errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
> > >
> > > While at it make return type of errata_probe_iocp() to void as we were
> > > not checking the return value in andes_errata_patch_func().
> > >
> > > Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
> > > Signed-off-by: Lad Prabhakar <[email protected]>
> > > ---
> > > v1->v2
> > > * As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
> > > variable to probe for IOCP only once.
> > > * Updated commit message
> > > * Make return value of errata_probe_iocp() to void
> >
> > Thanks for the update!
> >
> > > --- a/arch/riscv/errata/andes/errata.c
> > > +++ b/arch/riscv/errata/andes/errata.c
> > > @@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
> > > return ret.error ? 0 : ret.value;
> > > }
> > >
> > > -static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > +static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > {
> > > + static bool is_iocp_probe_done;
> >
> > done?
> >
> OK I'll rename it to "done".
>
> > > +
> > > if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> > > - return false;
> > > + return;
> > > +
> > > + if (is_iocp_probe_done)
> > > + return;
> > >
> >
> > Why not keep it simple, and just do
> >
> > done = true;
> >
> OK.
>
> > here?
> > Can arch_id or impid suddenly change, so you have to recheck?
> I only check arch_id and impid here. Are you suggesting I drop it?
No, I do not suggest to drop it.
I suggested moving the "done = true" up, so the check is done only once.
> > If the SBI call in ax45mp_iocp_sw_workaround() fails, is there really
> > a need to try it again later?
> >
> No if it fails we just continue with a broken system.
>
> Cheers,
> Prabhakar
> > > if (arch_id != ANDESTECH_AX45MP_MARCHID || impid != ANDESTECH_AX45MP_MIMPID)
> > > - return false;
> > > + return;
> > >
> > > - if (!ax45mp_iocp_sw_workaround())
> > > - return false;
> > > + if (!ax45mp_iocp_sw_workaround()) {
> > > + is_iocp_probe_done = true;
> > > + return;
> > > + }
> > >
> > > /* Set this just to make core cbo code happy */
> > > riscv_cbom_block_size = 1;
> > > riscv_noncoherent_supported();
> > > -
> > > - return true;
> > > + is_iocp_probe_done = true;
> > > }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
Hi Geert,
On Thu, Nov 30, 2023 at 4:26 PM Geert Uytterhoeven <[email protected]> wrote:
>
> Hi Prabhakar,
>
> On Thu, Nov 30, 2023 at 5:23 PM Lad, Prabhakar
> <[email protected]> wrote:
> > On Thu, Nov 30, 2023 at 2:34 PM Geert Uytterhoeven <[email protected]> wrote:
> > > On Thu, Nov 30, 2023 at 1:56 PM Prabhakar <[email protected]> wrote:
> > > > From: Lad Prabhakar <[email protected]>
> > > >
> > > > We need to probe for IOCP only once during boot stage, as we were probing
> > > > for IOCP for all the stages this caused the below issue during module-init
> > > > stage,
> > > >
> > > > [9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
> > > > [9.027153] Oops [#1]
> > > > [9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
> > > > [9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
> > > > [9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> > > > [9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
> > > > [9.055558] ra : andes_errata_patch_func+0x4a/0x52
> > > > [9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
> > > > [9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
> > > > [9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
> > > > [9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
> > > > [9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
> > > > [9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
> > > > [9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
> > > > [9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
> > > > [9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
> > > > [9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
> > > > [9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
> > > > [9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
> > > > [9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
> > > > [9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
> > > > [9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
> > > > [9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
> > > > [9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
> > > > [9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
> > > > [9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
> > > > [9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
> > > > [9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
> > > > [9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
> > > > [9.205994] ---[ end trace 0000000000000000 ]---
> > > >
> > > > This is because we called riscv_noncoherent_supported() for all the stages
> > > > during IOCP probe. riscv_noncoherent_supported() function sets
> > > > noncoherent_supported variable to true which has an annotation set to
> > > > "__ro_after_init" due to which we were seeing the above splat. Fix this by
> > > > probing for IOCP only once in boot stage by having a boolean variable
> > > > is_iocp_probe_done which will be set to true upon IOCP probe in
> > > > errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
> > > >
> > > > While at it make return type of errata_probe_iocp() to void as we were
> > > > not checking the return value in andes_errata_patch_func().
> > > >
> > > > Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
> > > > Signed-off-by: Lad Prabhakar <[email protected]>
> > > > ---
> > > > v1->v2
> > > > * As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
> > > > variable to probe for IOCP only once.
> > > > * Updated commit message
> > > > * Make return value of errata_probe_iocp() to void
> > >
> > > Thanks for the update!
> > >
> > > > --- a/arch/riscv/errata/andes/errata.c
> > > > +++ b/arch/riscv/errata/andes/errata.c
> > > > @@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
> > > > return ret.error ? 0 : ret.value;
> > > > }
> > > >
> > > > -static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > > +static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > > {
> > > > + static bool is_iocp_probe_done;
> > >
> > > done?
> > >
> > OK I'll rename it to "done".
> >
> > > > +
> > > > if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> > > > - return false;
> > > > + return;
> > > > +
> > > > + if (is_iocp_probe_done)
> > > > + return;
> > > >
> > >
> > > Why not keep it simple, and just do
> > >
> > > done = true;
> > >
> > OK.
> >
> > > here?
> > > Can arch_id or impid suddenly change, so you have to recheck?
> > I only check arch_id and impid here. Are you suggesting I drop it?
>
> No, I do not suggest to drop it.
> I suggested moving the "done = true" up, so the check is done only once.
>
OK, I'll have something like below:
static void errata_probe_iocp(unsigned int stage, unsigned long
arch_id, unsigned long impid)
{
static bool done;
if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
return;
if (done)
return;
if (arch_id != ANDES_AX45MP_MARCHID || impid != ANDES_AX45MP_MIMPID)
return;
done = true;
if (!ax45mp_iocp_sw_workaround())
return;
/* Set this just to make core cbo code happy */
riscv_cbom_block_size = 1;
riscv_noncoherent_supported();
}
Cheers,
Prabhakar
Hi Prabhakar,
On Thu, Nov 30, 2023 at 5:50 PM Lad, Prabhakar
<[email protected]> wrote:
> On Thu, Nov 30, 2023 at 4:26 PM Geert Uytterhoeven <[email protected]> wrote:
> > On Thu, Nov 30, 2023 at 5:23 PM Lad, Prabhakar
> > <[email protected]> wrote:
> > > On Thu, Nov 30, 2023 at 2:34 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > On Thu, Nov 30, 2023 at 1:56 PM Prabhakar <[email protected]> wrote:
> > > > > From: Lad Prabhakar <[email protected]>
> > > > >
> > > > > We need to probe for IOCP only once during boot stage, as we were probing
> > > > > for IOCP for all the stages this caused the below issue during module-init
> > > > > stage,
> > > > >
> > > > > [9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
> > > > > [9.027153] Oops [#1]
> > > > > [9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
> > > > > [9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
> > > > > [9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> > > > > [9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
> > > > > [9.055558] ra : andes_errata_patch_func+0x4a/0x52
> > > > > [9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
> > > > > [9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
> > > > > [9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
> > > > > [9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
> > > > > [9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
> > > > > [9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
> > > > > [9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
> > > > > [9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
> > > > > [9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
> > > > > [9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
> > > > > [9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
> > > > > [9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
> > > > > [9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
> > > > > [9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
> > > > > [9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
> > > > > [9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
> > > > > [9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
> > > > > [9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
> > > > > [9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
> > > > > [9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
> > > > > [9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
> > > > > [9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
> > > > > [9.205994] ---[ end trace 0000000000000000 ]---
> > > > >
> > > > > This is because we called riscv_noncoherent_supported() for all the stages
> > > > > during IOCP probe. riscv_noncoherent_supported() function sets
> > > > > noncoherent_supported variable to true which has an annotation set to
> > > > > "__ro_after_init" due to which we were seeing the above splat. Fix this by
> > > > > probing for IOCP only once in boot stage by having a boolean variable
> > > > > is_iocp_probe_done which will be set to true upon IOCP probe in
> > > > > errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
> > > > >
> > > > > While at it make return type of errata_probe_iocp() to void as we were
> > > > > not checking the return value in andes_errata_patch_func().
> > > > >
> > > > > Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
> > > > > Signed-off-by: Lad Prabhakar <[email protected]>
> > > > > ---
> > > > > v1->v2
> > > > > * As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
> > > > > variable to probe for IOCP only once.
> > > > > * Updated commit message
> > > > > * Make return value of errata_probe_iocp() to void
> > > >
> > > > Thanks for the update!
> > > >
> > > > > --- a/arch/riscv/errata/andes/errata.c
> > > > > +++ b/arch/riscv/errata/andes/errata.c
> > > > > @@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
> > > > > return ret.error ? 0 : ret.value;
> > > > > }
> > > > >
> > > > > -static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > > > +static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > > > {
> > > > > + static bool is_iocp_probe_done;
> > > >
> > > > done?
> > > >
> > > OK I'll rename it to "done".
> > >
> > > > > +
> > > > > if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> > > > > - return false;
> > > > > + return;
> > > > > +
> > > > > + if (is_iocp_probe_done)
> > > > > + return;
> > > > >
> > > >
> > > > Why not keep it simple, and just do
> > > >
> > > > done = true;
> > > >
> > > OK.
> > >
> > > > here?
> > > > Can arch_id or impid suddenly change, so you have to recheck?
> > > I only check arch_id and impid here. Are you suggesting I drop it?
> >
> > No, I do not suggest to drop it.
> > I suggested moving the "done = true" up, so the check is done only once.
> >
> OK, I'll have something like below:
>
> static void errata_probe_iocp(unsigned int stage, unsigned long
> arch_id, unsigned long impid)
> {
> static bool done;
>
> if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> return;
>
> if (done)
> return;
>
> if (arch_id != ANDES_AX45MP_MARCHID || impid != ANDES_AX45MP_MIMPID)
> return;
Please move this check below "done = true", as there is no need to
execute this check multiple times.
> done = true;
>
> if (!ax45mp_iocp_sw_workaround())
> return;
>
> /* Set this just to make core cbo code happy */
> riscv_cbom_block_size = 1;
> riscv_noncoherent_supported();
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
Hi Geert,
On Thu, Nov 30, 2023 at 4:54 PM Geert Uytterhoeven <[email protected]> wrote:
>
> Hi Prabhakar,
>
> On Thu, Nov 30, 2023 at 5:50 PM Lad, Prabhakar
> <[email protected]> wrote:
> > On Thu, Nov 30, 2023 at 4:26 PM Geert Uytterhoeven <[email protected]> wrote:
> > > On Thu, Nov 30, 2023 at 5:23 PM Lad, Prabhakar
> > > <[email protected]> wrote:
> > > > On Thu, Nov 30, 2023 at 2:34 PM Geert Uytterhoeven <[email protected]> wrote:
> > > > > On Thu, Nov 30, 2023 at 1:56 PM Prabhakar <[email protected]> wrote:
> > > > > > From: Lad Prabhakar <[email protected]>
> > > > > >
> > > > > > We need to probe for IOCP only once during boot stage, as we were probing
> > > > > > for IOCP for all the stages this caused the below issue during module-init
> > > > > > stage,
> > > > > >
> > > > > > [9.019104] Unable to handle kernel paging request at virtual address ffffffff8100d3a0
> > > > > > [9.027153] Oops [#1]
> > > > > > [9.029421] Modules linked in: rcar_canfd renesas_usbhs i2c_riic can_dev spi_rspi i2c_core
> > > > > > [9.037686] CPU: 0 PID: 90 Comm: udevd Not tainted 6.7.0-rc1+ #57
> > > > > > [9.043756] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> > > > > > [9.050339] epc : riscv_noncoherent_supported+0x10/0x3e
> > > > > > [9.055558] ra : andes_errata_patch_func+0x4a/0x52
> > > > > > [9.060418] epc : ffffffff8000d8c2 ra : ffffffff8000d95c sp : ffffffc8003abb00
> > > > > > [9.067607] gp : ffffffff814e25a0 tp : ffffffd80361e540 t0 : 0000000000000000
> > > > > > [9.074795] t1 : 000000000900031e t2 : 0000000000000001 s0 : ffffffc8003abb20
> > > > > > [9.081984] s1 : ffffffff015b57c7 a0 : 0000000000000000 a1 : 0000000000000001
> > > > > > [9.089172] a2 : 0000000000000000 a3 : 0000000000000000 a4 : ffffffff8100d8be
> > > > > > [9.096360] a5 : 0000000000000001 a6 : 0000000000000001 a7 : 000000000900031e
> > > > > > [9.103548] s2 : ffffffff015b57d7 s3 : 0000000000000001 s4 : 000000000000031e
> > > > > > [9.110736] s5 : 8000000000008a45 s6 : 0000000000000500 s7 : 000000000000003f
> > > > > > [9.117924] s8 : ffffffc8003abd48 s9 : ffffffff015b1140 s10: ffffffff8151a1b0
> > > > > > [9.125113] s11: ffffffff015b1000 t3 : 0000000000000001 t4 : fefefefefefefeff
> > > > > > [9.132301] t5 : ffffffff015b57c7 t6 : ffffffd8b63a6000
> > > > > > [9.137587] status: 0000000200000120 badaddr: ffffffff8100d3a0 cause: 000000000000000f
> > > > > > [9.145468] [<ffffffff8000d8c2>] riscv_noncoherent_supported+0x10/0x3e
> > > > > > [9.151972] [<ffffffff800027e8>] _apply_alternatives+0x84/0x86
> > > > > > [9.157784] [<ffffffff800029be>] apply_module_alternatives+0x10/0x1a
> > > > > > [9.164113] [<ffffffff80008fcc>] module_finalize+0x5e/0x7a
> > > > > > [9.169583] [<ffffffff80085cd6>] load_module+0xfd8/0x179c
> > > > > > [9.174965] [<ffffffff80086630>] init_module_from_file+0x76/0xaa
> > > > > > [9.180948] [<ffffffff800867f6>] __riscv_sys_finit_module+0x176/0x2a8
> > > > > > [9.187365] [<ffffffff80889862>] do_trap_ecall_u+0xbe/0x130
> > > > > > [9.192922] [<ffffffff808920bc>] ret_from_exception+0x0/0x64
> > > > > > [9.198573] Code: 0009 b7e9 6797 014d a783 85a7 c799 4785 0717 0100 (0123) aef7
> > > > > > [9.205994] ---[ end trace 0000000000000000 ]---
> > > > > >
> > > > > > This is because we called riscv_noncoherent_supported() for all the stages
> > > > > > during IOCP probe. riscv_noncoherent_supported() function sets
> > > > > > noncoherent_supported variable to true which has an annotation set to
> > > > > > "__ro_after_init" due to which we were seeing the above splat. Fix this by
> > > > > > probing for IOCP only once in boot stage by having a boolean variable
> > > > > > is_iocp_probe_done which will be set to true upon IOCP probe in
> > > > > > errata_probe_iocp() and we bail out early if is_iocp_probe_done is set.
> > > > > >
> > > > > > While at it make return type of errata_probe_iocp() to void as we were
> > > > > > not checking the return value in andes_errata_patch_func().
> > > > > >
> > > > > > Fixes: e021ae7f5145 ("riscv: errata: Add Andes alternative ports")
> > > > > > Signed-off-by: Lad Prabhakar <[email protected]>
> > > > > > ---
> > > > > > v1->v2
> > > > > > * As RISCV_ALTERNATIVES_BOOT stage can happen twice add a is_iocp_probe_done
> > > > > > variable to probe for IOCP only once.
> > > > > > * Updated commit message
> > > > > > * Make return value of errata_probe_iocp() to void
> > > > >
> > > > > Thanks for the update!
> > > > >
> > > > > > --- a/arch/riscv/errata/andes/errata.c
> > > > > > +++ b/arch/riscv/errata/andes/errata.c
> > > > > > @@ -38,29 +38,36 @@ static long ax45mp_iocp_sw_workaround(void)
> > > > > > return ret.error ? 0 : ret.value;
> > > > > > }
> > > > > >
> > > > > > -static bool errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > > > > +static void errata_probe_iocp(unsigned int stage, unsigned long arch_id, unsigned long impid)
> > > > > > {
> > > > > > + static bool is_iocp_probe_done;
> > > > >
> > > > > done?
> > > > >
> > > > OK I'll rename it to "done".
> > > >
> > > > > > +
> > > > > > if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> > > > > > - return false;
> > > > > > + return;
> > > > > > +
> > > > > > + if (is_iocp_probe_done)
> > > > > > + return;
> > > > > >
> > > > >
> > > > > Why not keep it simple, and just do
> > > > >
> > > > > done = true;
> > > > >
> > > > OK.
> > > >
> > > > > here?
> > > > > Can arch_id or impid suddenly change, so you have to recheck?
> > > > I only check arch_id and impid here. Are you suggesting I drop it?
> > >
> > > No, I do not suggest to drop it.
> > > I suggested moving the "done = true" up, so the check is done only once.
> > >
> > OK, I'll have something like below:
> >
> > static void errata_probe_iocp(unsigned int stage, unsigned long
> > arch_id, unsigned long impid)
> > {
> > static bool done;
> >
> > if (!IS_ENABLED(CONFIG_ERRATA_ANDES_CMO))
> > return;
> >
> > if (done)
> > return;
> >
> > if (arch_id != ANDES_AX45MP_MARCHID || impid != ANDES_AX45MP_MIMPID)
> > return;
>
> Please move this check below "done = true", as there is no need to
> execute this check multiple times.
>
OK, will do.
Cheers,
Prabhakar