| Message ID | 20200202110202.124048-1-anup.patel@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | RISC-V: Don't enable all interrupts in trap_init() | expand |
On Sun, Feb 2, 2020 at 3:06 AM Anup Patel <anup.patel@wdc.com> wrote: > > Historically, we have been enabling all interrupts for each > HART in trap_init(). Ideally, we should only enable M-mode > interrupts for M-mode kernel and S-mode interrupts for S-mode > kernel in trap_init(). > > Currently, we get suprious S-mode interrupts on Kendryte K210 > board running M-mode NO-MMU kernel because we are enabling all > interrupts in trap_init(). To fix this, we only enable software > and external interrupt in trap_init(). In future, trap_init() > will only enable software interrupt and PLIC driver will enable > external interrupt using CPU notifiers. > > Cc: stable@vger.kernel.org > Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code) > Signed-off-by: Anup Patel <anup.patel@wdc.com> > --- > arch/riscv/kernel/traps.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c > index f4cad5163bf2..ffb3d94bf0cc 100644 > --- a/arch/riscv/kernel/traps.c > +++ b/arch/riscv/kernel/traps.c > @@ -156,6 +156,6 @@ void __init trap_init(void) > csr_write(CSR_SCRATCH, 0); > /* Set the exception vector address */ > csr_write(CSR_TVEC, &handle_exception); > - /* Enable all interrupts */ > - csr_write(CSR_IE, -1); > + /* Enable interrupts */ > + csr_write(CSR_IE, IE_SIE | IE_EIE); > } > -- > 2.17.1 > > Looks good. Reviewed-by: Atish Patra <atish.patra@wdc.com>
On Sun, 02 Feb 2020 03:48:18 PST (-0800), atishp@atishpatra.org wrote: > On Sun, Feb 2, 2020 at 3:06 AM Anup Patel <anup.patel@wdc.com> wrote: >> >> Historically, we have been enabling all interrupts for each >> HART in trap_init(). Ideally, we should only enable M-mode >> interrupts for M-mode kernel and S-mode interrupts for S-mode >> kernel in trap_init(). >> >> Currently, we get suprious S-mode interrupts on Kendryte K210 >> board running M-mode NO-MMU kernel because we are enabling all >> interrupts in trap_init(). To fix this, we only enable software >> and external interrupt in trap_init(). In future, trap_init() >> will only enable software interrupt and PLIC driver will enable >> external interrupt using CPU notifiers. I think we should add a proper interrupt controller driver for the per-hart interrupt controllers, as doing this within the other drivers is ugly -- for example, there's no reason an MMIO timer or interrupt controller driver should be toggling these bits. >> Cc: stable@vger.kernel.org >> Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code) I'd argue this actually fixes the M-mode stuff, since that's the first place this issue shows up. I've queued this with Fixes: a4c3733d32a7 ("riscv: abstract out CSR names for supervisor vs machine mode") instead, as that's the first commit that will actually write to MIE and therefor the first commit that will actually exhibit bad behavior. It also has the advantage of making the patch apply on older trees, which should make life easier for the stable folks. >> Signed-off-by: Anup Patel <anup.patel@wdc.com> >> --- >> arch/riscv/kernel/traps.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c >> index f4cad5163bf2..ffb3d94bf0cc 100644 >> --- a/arch/riscv/kernel/traps.c >> +++ b/arch/riscv/kernel/traps.c >> @@ -156,6 +156,6 @@ void __init trap_init(void) >> csr_write(CSR_SCRATCH, 0); >> /* Set the exception vector address */ >> csr_write(CSR_TVEC, &handle_exception); >> - /* Enable all interrupts */ >> - csr_write(CSR_IE, -1); >> + /* Enable interrupts */ >> + csr_write(CSR_IE, IE_SIE | IE_EIE); >> } >> -- >> 2.17.1 >> >> > > Looks good. > Reviewed-by: Atish Patra <atish.patra@wdc.com> Tested-by: Palmer Dabbelt <palmerdabbelt@google.com> [QMEU virt machine with SMP] Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> I consider this a bugfix, so I'm targeting it for RCs. It's on fixes and should go up this week. Thanks!
On Wed, Feb 19, 2020 at 12:06 AM Palmer Dabbelt <palmer@dabbelt.com> wrote: > > On Sun, 02 Feb 2020 03:48:18 PST (-0800), atishp@atishpatra.org wrote: > > On Sun, Feb 2, 2020 at 3:06 AM Anup Patel <anup.patel@wdc.com> wrote: > >> > >> Historically, we have been enabling all interrupts for each > >> HART in trap_init(). Ideally, we should only enable M-mode > >> interrupts for M-mode kernel and S-mode interrupts for S-mode > >> kernel in trap_init(). > >> > >> Currently, we get suprious S-mode interrupts on Kendryte K210 > >> board running M-mode NO-MMU kernel because we are enabling all > >> interrupts in trap_init(). To fix this, we only enable software > >> and external interrupt in trap_init(). In future, trap_init() > >> will only enable software interrupt and PLIC driver will enable > >> external interrupt using CPU notifiers. > > I think we should add a proper interrupt controller driver for the per-hart > interrupt controllers, as doing this within the other drivers is ugly -- for > example, there's no reason an MMIO timer or interrupt controller driver should > be toggling these bits. I have always been in support of having per-hart interrupt controller driver. I will rebase my RISC-V INTC driver upon latest kernel and send it again. Of course, now the situation has changed the RISC-V INTC driver will have to consider NOMMU kernel as well. The last version of RISC-V INTC driver can be found in riscv_intc_v2 branch of https://github.com/avpatel/linux.git > > >> Cc: stable@vger.kernel.org > >> Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code) > > I'd argue this actually fixes the M-mode stuff, since that's the first place > this issue shows up. I've queued this with > > Fixes: a4c3733d32a7 ("riscv: abstract out CSR names for supervisor vs machine mode") > > instead, as that's the first commit that will actually write to MIE and > therefor the first commit that will actually exhibit bad behavior. It also has > the advantage of making the patch apply on older trees, which should make life > easier for the stable folks. Sure, no problem. > > >> Signed-off-by: Anup Patel <anup.patel@wdc.com> > >> --- > >> arch/riscv/kernel/traps.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c > >> index f4cad5163bf2..ffb3d94bf0cc 100644 > >> --- a/arch/riscv/kernel/traps.c > >> +++ b/arch/riscv/kernel/traps.c > >> @@ -156,6 +156,6 @@ void __init trap_init(void) > >> csr_write(CSR_SCRATCH, 0); > >> /* Set the exception vector address */ > >> csr_write(CSR_TVEC, &handle_exception); > >> - /* Enable all interrupts */ > >> - csr_write(CSR_IE, -1); > >> + /* Enable interrupts */ > >> + csr_write(CSR_IE, IE_SIE | IE_EIE); > >> } > >> -- > >> 2.17.1 > >> > >> > > > > Looks good. > > Reviewed-by: Atish Patra <atish.patra@wdc.com> > > Tested-by: Palmer Dabbelt <palmerdabbelt@google.com> [QMEU virt machine with SMP] > Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> > > I consider this a bugfix, so I'm targeting it for RCs. It's on fixes and > should go up this week. > > Thanks! Thanks, Anup
On Tue, 18 Feb 2020 19:28:38 PST (-0800), anup@brainfault.org wrote: > On Wed, Feb 19, 2020 at 12:06 AM Palmer Dabbelt <palmer@dabbelt.com> wrote: >> >> On Sun, 02 Feb 2020 03:48:18 PST (-0800), atishp@atishpatra.org wrote: >> > On Sun, Feb 2, 2020 at 3:06 AM Anup Patel <anup.patel@wdc.com> wrote: >> >> >> >> Historically, we have been enabling all interrupts for each >> >> HART in trap_init(). Ideally, we should only enable M-mode >> >> interrupts for M-mode kernel and S-mode interrupts for S-mode >> >> kernel in trap_init(). >> >> >> >> Currently, we get suprious S-mode interrupts on Kendryte K210 >> >> board running M-mode NO-MMU kernel because we are enabling all >> >> interrupts in trap_init(). To fix this, we only enable software >> >> and external interrupt in trap_init(). In future, trap_init() >> >> will only enable software interrupt and PLIC driver will enable >> >> external interrupt using CPU notifiers. >> >> I think we should add a proper interrupt controller driver for the per-hart >> interrupt controllers, as doing this within the other drivers is ugly -- for >> example, there's no reason an MMIO timer or interrupt controller driver should >> be toggling these bits. > > I have always been in support of having per-hart interrupt controller driver. > > I will rebase my RISC-V INTC driver upon latest kernel and send it again. > Of course, now the situation has changed the RISC-V INTC driver will > have to consider NOMMU kernel as well. > > The last version of RISC-V INTC driver can be found in riscv_intc_v2 > branch of https://github.com/avpatel/linux.git Thanks. I think I saw some patches go by, so let's talk over there. > >> >> >> Cc: stable@vger.kernel.org >> >> Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code) >> >> I'd argue this actually fixes the M-mode stuff, since that's the first place >> this issue shows up. I've queued this with >> >> Fixes: a4c3733d32a7 ("riscv: abstract out CSR names for supervisor vs machine mode") >> >> instead, as that's the first commit that will actually write to MIE and >> therefor the first commit that will actually exhibit bad behavior. It also has >> the advantage of making the patch apply on older trees, which should make life >> easier for the stable folks. > > Sure, no problem. > >> >> >> Signed-off-by: Anup Patel <anup.patel@wdc.com> >> >> --- >> >> arch/riscv/kernel/traps.c | 4 ++-- >> >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> >> >> diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c >> >> index f4cad5163bf2..ffb3d94bf0cc 100644 >> >> --- a/arch/riscv/kernel/traps.c >> >> +++ b/arch/riscv/kernel/traps.c >> >> @@ -156,6 +156,6 @@ void __init trap_init(void) >> >> csr_write(CSR_SCRATCH, 0); >> >> /* Set the exception vector address */ >> >> csr_write(CSR_TVEC, &handle_exception); >> >> - /* Enable all interrupts */ >> >> - csr_write(CSR_IE, -1); >> >> + /* Enable interrupts */ >> >> + csr_write(CSR_IE, IE_SIE | IE_EIE); >> >> } >> >> -- >> >> 2.17.1 >> >> >> >> >> > >> > Looks good. >> > Reviewed-by: Atish Patra <atish.patra@wdc.com> >> >> Tested-by: Palmer Dabbelt <palmerdabbelt@google.com> [QMEU virt machine with SMP] >> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> >> >> I consider this a bugfix, so I'm targeting it for RCs. It's on fixes and >> should go up this week. >> >> Thanks! > > Thanks, > Anup
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index f4cad5163bf2..ffb3d94bf0cc 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -156,6 +156,6 @@ void __init trap_init(void) csr_write(CSR_SCRATCH, 0); /* Set the exception vector address */ csr_write(CSR_TVEC, &handle_exception); - /* Enable all interrupts */ - csr_write(CSR_IE, -1); + /* Enable interrupts */ + csr_write(CSR_IE, IE_SIE | IE_EIE); }
Historically, we have been enabling all interrupts for each HART in trap_init(). Ideally, we should only enable M-mode interrupts for M-mode kernel and S-mode interrupts for S-mode kernel in trap_init(). Currently, we get suprious S-mode interrupts on Kendryte K210 board running M-mode NO-MMU kernel because we are enabling all interrupts in trap_init(). To fix this, we only enable software and external interrupt in trap_init(). In future, trap_init() will only enable software interrupt and PLIC driver will enable external interrupt using CPU notifiers. Cc: stable@vger.kernel.org Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code) Signed-off-by: Anup Patel <anup.patel@wdc.com> --- arch/riscv/kernel/traps.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)