| Message ID | 20211129185751.25355-1-leandro.lupori@eldorado.org.br (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] target/ppc: fix Hash64 MMU update of PTE bit R | expand |
On Mon, Nov 29, 2021 at 03:57:51PM -0300, Leandro Lupori wrote: > When updating the R bit of a PTE, the Hash64 MMU was using a wrong byte > offset, causing the first byte of the adjacent PTE to be corrupted. > This caused a panic when booting FreeBSD, using the Hash MMU. > > Fixes: a2dd4e83e76b ("ppc/hash64: Rework R and C bit updates") > Signed-off-by: Leandro Lupori <leandro.lupori@eldorado.org.br> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Thanks for your patience with our nitpicking :). > --- > Changes from v3: > - rename defines > --- > hw/ppc/spapr.c | 8 ++++---- > hw/ppc/spapr_softmmu.c | 2 +- > target/ppc/mmu-hash64.c | 4 ++-- > target/ppc/mmu-hash64.h | 5 +++++ > 4 files changed, 12 insertions(+), 7 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 163c90388a..3b5fd749be 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -1414,7 +1414,7 @@ void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, > kvmppc_write_hpte(ptex, pte0, pte1); > } else { > if (pte0 & HPTE64_V_VALID) { > - stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1); > + stq_p(spapr->htab + offset + HPTE64_DW1, pte1); > /* > * When setting valid, we write PTE1 first. This ensures > * proper synchronization with the reading code in > @@ -1430,7 +1430,7 @@ void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, > * ppc_hash64_pteg_search() > */ > smp_wmb(); > - stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1); > + stq_p(spapr->htab + offset + HPTE64_DW1, pte1); > } > } > } > @@ -1438,7 +1438,7 @@ void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, > static void spapr_hpte_set_c(PPCVirtualHypervisor *vhyp, hwaddr ptex, > uint64_t pte1) > { > - hwaddr offset = ptex * HASH_PTE_SIZE_64 + 15; > + hwaddr offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_C; > SpaprMachineState *spapr = SPAPR_MACHINE(vhyp); > > if (!spapr->htab) { > @@ -1454,7 +1454,7 @@ static void spapr_hpte_set_c(PPCVirtualHypervisor *vhyp, hwaddr ptex, > static void spapr_hpte_set_r(PPCVirtualHypervisor *vhyp, hwaddr ptex, > uint64_t pte1) > { > - hwaddr offset = ptex * HASH_PTE_SIZE_64 + 14; > + hwaddr offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_R; > SpaprMachineState *spapr = SPAPR_MACHINE(vhyp); > > if (!spapr->htab) { > diff --git a/hw/ppc/spapr_softmmu.c b/hw/ppc/spapr_softmmu.c > index f8924270ef..4ee03c83e4 100644 > --- a/hw/ppc/spapr_softmmu.c > +++ b/hw/ppc/spapr_softmmu.c > @@ -426,7 +426,7 @@ static void new_hpte_store(void *htab, uint64_t pteg, int slot, > addr += slot * HASH_PTE_SIZE_64; > > stq_p(addr, pte0); > - stq_p(addr + HASH_PTE_SIZE_64 / 2, pte1); > + stq_p(addr + HPTE64_DW1, pte1); > } > > static int rehash_hpte(PowerPCCPU *cpu, > diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c > index 19832c4b46..da9fe99ff8 100644 > --- a/target/ppc/mmu-hash64.c > +++ b/target/ppc/mmu-hash64.c > @@ -786,7 +786,7 @@ static void ppc_hash64_set_dsi(CPUState *cs, int mmu_idx, uint64_t dar, uint64_t > > static void ppc_hash64_set_r(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1) > { > - hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + 16; > + hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_R; > > if (cpu->vhyp) { > PPCVirtualHypervisorClass *vhc = > @@ -803,7 +803,7 @@ static void ppc_hash64_set_r(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1) > > static void ppc_hash64_set_c(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1) > { > - hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + 15; > + hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_C; > > if (cpu->vhyp) { > PPCVirtualHypervisorClass *vhc = > diff --git a/target/ppc/mmu-hash64.h b/target/ppc/mmu-hash64.h > index c5b2f97ff7..1496955d38 100644 > --- a/target/ppc/mmu-hash64.h > +++ b/target/ppc/mmu-hash64.h > @@ -97,6 +97,11 @@ void ppc_hash64_finalize(PowerPCCPU *cpu); > #define HPTE64_V_1TB_SEG 0x4000000000000000ULL > #define HPTE64_V_VRMA_MASK 0x4001ffffff000000ULL > > +/* PTE offsets */ > +#define HPTE64_DW1 (HASH_PTE_SIZE_64 / 2) > +#define HPTE64_DW1_R (HPTE64_DW1 + 6) > +#define HPTE64_DW1_C (HPTE64_DW1 + 7) > + > /* Format changes for ARCH v3 */ > #define HPTE64_V_COMMON_BITS 0x000fffffffffffffULL > #define HPTE64_R_3_0_SSIZE_SHIFT 58
On 11/30/21 01:30, David Gibson wrote: > On Mon, Nov 29, 2021 at 03:57:51PM -0300, Leandro Lupori wrote: >> When updating the R bit of a PTE, the Hash64 MMU was using a wrong byte >> offset, causing the first byte of the adjacent PTE to be corrupted. >> This caused a panic when booting FreeBSD, using the Hash MMU. >> >> Fixes: a2dd4e83e76b ("ppc/hash64: Rework R and C bit updates") >> Signed-off-by: Leandro Lupori <leandro.lupori@eldorado.org.br> > > Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Sorry, I didn't wait for your Rb because the patch was a good candidate for -rc3. It is merged now. > Thanks for your patience with our nitpicking :). Yes, Here is another QEMU bug found by FreeBSD : https://lore.kernel.org/qemu-devel/427ef2ee-6871-0d27-f485-90ad142f6266@kaod.org/ It would be interesting to boot directly the PowerNV machine from a FreeBSB kernel and a minimum inirtd without using the skiroot images and an iso. Are images available ? Thanks. C.
On 30/11/2021 05:44, Cédric Le Goater wrote: > It would be interesting to boot directly the PowerNV machine from a > FreeBSB kernel and a minimum inirtd without using the skiroot images > and an iso. Are images available ? AFAIK there are no minimum initrd images available. The closest thing would be the "bootonly" ISOs that can be found in the links below: https://download.freebsd.org/ftp/releases/powerpc/powerpc64/ISO-IMAGES/13.0/ https://download.freebsd.org/ftp/releases/powerpc/powerpc64le/ISO-IMAGES/13.0/ https://download.freebsd.org/ftp/snapshots/powerpc/powerpc64/ISO-IMAGES/14.0/ https://download.freebsd.org/ftp/snapshots/powerpc/powerpc64le/ISO-IMAGES/14.0/ But to avoid using skiroot, you would need to manually extract the kernel from the ISO and also specify the rootfs, using something like: "-append cd9660:cd0". If you don't want to emulate a disk or cd, the ISO can be passed to -initrd and "-append cd9660:md0" may be used to tell FreeBSD where to find the root partition (it loads it as a memory disk). There are also qcow2 snapshots available: https://artifact.ci.freebsd.org/snapshot/14.0-CURRENT/latest/powerpc/powerpc64/ https://artifact.ci.freebsd.org/snapshot/14.0-CURRENT/latest/powerpc/powerpc64le/ But you'll also need to extract the kernel from the image or from kernel.txz to boot them. As these images target pseries and lack a FAT32 partition, Petitboot won't be able to boot them. Alfredo (cc'ed) was trying to make them Petitboot compatible.
On Tue, Nov 30, 2021 at 09:44:58AM +0100, Cédric le Goater wrote: > On 11/30/21 01:30, David Gibson wrote: > > On Mon, Nov 29, 2021 at 03:57:51PM -0300, Leandro Lupori wrote: > > > When updating the R bit of a PTE, the Hash64 MMU was using a wrong byte > > > offset, causing the first byte of the adjacent PTE to be corrupted. > > > This caused a panic when booting FreeBSD, using the Hash MMU. > > > > > > Fixes: a2dd4e83e76b ("ppc/hash64: Rework R and C bit updates") > > > Signed-off-by: Leandro Lupori <leandro.lupori@eldorado.org.br> > > > > Reviewed-by: David Gibson <david@gibson.dropbear.id.au> > > Sorry, I didn't wait for your Rb because the patch was a good candidate > for -rc3. It is merged now. No worries. > > > Thanks for your patience with our nitpicking :). > > Yes, > > Here is another QEMU bug found by FreeBSD : > https://lore.kernel.org/qemu-devel/427ef2ee-6871-0d27-f485-90ad142f6266@kaod.org/ > > It would be interesting to boot directly the PowerNV machine from a > FreeBSB kernel and a minimum inirtd without using the skiroot images > and an iso. Are images available ? > > Thanks. > > C. >
On 11/30/21 21:00, Leandro Lupori wrote: > On 30/11/2021 05:44, Cédric Le Goater wrote: >> It would be interesting to boot directly the PowerNV machine from a >> FreeBSB kernel and a minimum inirtd without using the skiroot images >> and an iso. Are images available ? > > AFAIK there are no minimum initrd images available. The closest thing would be the "bootonly" ISOs that can be found in the links below: > > https://download.freebsd.org/ftp/releases/powerpc/powerpc64/ISO-IMAGES/13.0/ > > https://download.freebsd.org/ftp/releases/powerpc/powerpc64le/ISO-IMAGES/13.0/ > > https://download.freebsd.org/ftp/snapshots/powerpc/powerpc64/ISO-IMAGES/14.0/ > > https://download.freebsd.org/ftp/snapshots/powerpc/powerpc64le/ISO-IMAGES/14.0/ > > > But to avoid using skiroot, you would need to manually extract the kernel from the ISO and also specify the rootfs, using something like: "-append cd9660:cd0". > If you don't want to emulate a disk or cd, the ISO can be passed to -initrd and "-append cd9660:md0" may be used to tell FreeBSD where to find the root partition (it loads it as a memory disk). The ISO is too big for quick tests. Isn't there a minimum initrd ? can we build a builroot-like image for FreeBSD ? > > There are also qcow2 snapshots available: > > https://artifact.ci.freebsd.org/snapshot/14.0-CURRENT/latest/powerpc/powerpc64/ > > https://artifact.ci.freebsd.org/snapshot/14.0-CURRENT/latest/powerpc/powerpc64le/ > > But you'll also need to extract the kernel from the image or from kernel.txz to boot them. ok. I will take a look. > As these images target pseries and lack a FAT32 partition, Petitboot won't be able to boot them. The idea would be to skip petitboot and load directly the FreeBSD kernel from skiboot with a minimum initrd or disk image. See : https://github.com/legoater/qemu-ppc-boot/blob/main/buildroot/qemu_ppc64le_powernv-2021.11-rc1-199-g927444a04e-20211120/start-qemu.sh or https://github.com/legoater/qemu-ppc-boot/blob/main/buildroot/qemu_ppc64le_pseries-2021.11-rc1-199-g927444a04e-20211120/start-qemu.sh Thanks, C. > > Alfredo (cc'ed) was trying to make them Petitboot compatible. >
On 01/12/2021 04:51, Cédric Le Goater wrote: > The ISO is too big for quick tests. Isn't there a minimum initrd ? can > we build a > builroot-like image for FreeBSD ? > FreeBSD doesn't use initrd. Its bootloader loads kernel modules directly from disk (unfortunately, it doesn't work on PowerNV). But it's possible to build a minimum disk image and make FreeBSD load it as a ramdisk, by passing it through QEMU's -initrd (even though it's not an initrd). By default FreeBSD builds a program called rescue, that is similar to busybox, that would help when building a minimum image.
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 163c90388a..3b5fd749be 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -1414,7 +1414,7 @@ void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, kvmppc_write_hpte(ptex, pte0, pte1); } else { if (pte0 & HPTE64_V_VALID) { - stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1); + stq_p(spapr->htab + offset + HPTE64_DW1, pte1); /* * When setting valid, we write PTE1 first. This ensures * proper synchronization with the reading code in @@ -1430,7 +1430,7 @@ void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, * ppc_hash64_pteg_search() */ smp_wmb(); - stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1); + stq_p(spapr->htab + offset + HPTE64_DW1, pte1); } } } @@ -1438,7 +1438,7 @@ void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, static void spapr_hpte_set_c(PPCVirtualHypervisor *vhyp, hwaddr ptex, uint64_t pte1) { - hwaddr offset = ptex * HASH_PTE_SIZE_64 + 15; + hwaddr offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_C; SpaprMachineState *spapr = SPAPR_MACHINE(vhyp); if (!spapr->htab) { @@ -1454,7 +1454,7 @@ static void spapr_hpte_set_c(PPCVirtualHypervisor *vhyp, hwaddr ptex, static void spapr_hpte_set_r(PPCVirtualHypervisor *vhyp, hwaddr ptex, uint64_t pte1) { - hwaddr offset = ptex * HASH_PTE_SIZE_64 + 14; + hwaddr offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_R; SpaprMachineState *spapr = SPAPR_MACHINE(vhyp); if (!spapr->htab) { diff --git a/hw/ppc/spapr_softmmu.c b/hw/ppc/spapr_softmmu.c index f8924270ef..4ee03c83e4 100644 --- a/hw/ppc/spapr_softmmu.c +++ b/hw/ppc/spapr_softmmu.c @@ -426,7 +426,7 @@ static void new_hpte_store(void *htab, uint64_t pteg, int slot, addr += slot * HASH_PTE_SIZE_64; stq_p(addr, pte0); - stq_p(addr + HASH_PTE_SIZE_64 / 2, pte1); + stq_p(addr + HPTE64_DW1, pte1); } static int rehash_hpte(PowerPCCPU *cpu, diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c index 19832c4b46..da9fe99ff8 100644 --- a/target/ppc/mmu-hash64.c +++ b/target/ppc/mmu-hash64.c @@ -786,7 +786,7 @@ static void ppc_hash64_set_dsi(CPUState *cs, int mmu_idx, uint64_t dar, uint64_t static void ppc_hash64_set_r(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1) { - hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + 16; + hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_R; if (cpu->vhyp) { PPCVirtualHypervisorClass *vhc = @@ -803,7 +803,7 @@ static void ppc_hash64_set_r(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1) static void ppc_hash64_set_c(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1) { - hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + 15; + hwaddr base, offset = ptex * HASH_PTE_SIZE_64 + HPTE64_DW1_C; if (cpu->vhyp) { PPCVirtualHypervisorClass *vhc = diff --git a/target/ppc/mmu-hash64.h b/target/ppc/mmu-hash64.h index c5b2f97ff7..1496955d38 100644 --- a/target/ppc/mmu-hash64.h +++ b/target/ppc/mmu-hash64.h @@ -97,6 +97,11 @@ void ppc_hash64_finalize(PowerPCCPU *cpu); #define HPTE64_V_1TB_SEG 0x4000000000000000ULL #define HPTE64_V_VRMA_MASK 0x4001ffffff000000ULL +/* PTE offsets */ +#define HPTE64_DW1 (HASH_PTE_SIZE_64 / 2) +#define HPTE64_DW1_R (HPTE64_DW1 + 6) +#define HPTE64_DW1_C (HPTE64_DW1 + 7) + /* Format changes for ARCH v3 */ #define HPTE64_V_COMMON_BITS 0x000fffffffffffffULL #define HPTE64_R_3_0_SSIZE_SHIFT 58
When updating the R bit of a PTE, the Hash64 MMU was using a wrong byte offset, causing the first byte of the adjacent PTE to be corrupted. This caused a panic when booting FreeBSD, using the Hash MMU. Fixes: a2dd4e83e76b ("ppc/hash64: Rework R and C bit updates") Signed-off-by: Leandro Lupori <leandro.lupori@eldorado.org.br> --- Changes from v3: - rename defines --- hw/ppc/spapr.c | 8 ++++---- hw/ppc/spapr_softmmu.c | 2 +- target/ppc/mmu-hash64.c | 4 ++-- target/ppc/mmu-hash64.h | 5 +++++ 4 files changed, 12 insertions(+), 7 deletions(-)