On 10.12.2012, at 10:18, Cornelia Huck wrote: > On Mon, 10 Dec 2012 10:00:16 +0100 > Alexander Graf <agraf@xxxxxxx> wrote: > >> >> >> On 07.12.2012, at 13:50, Cornelia Huck <cornelia.huck@xxxxxxxxxx> wrote: >> >>> Provide handlers for (most) channel I/O instructions. >>> >>> Signed-off-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> >>> --- >>> target-s390x/cpu.h | 87 +++++++ >>> target-s390x/ioinst.c | 694 +++++++++++++++++++++++++++++++++++++++++++++++++- >>> target-s390x/ioinst.h | 16 ++ >>> trace-events | 6 + >>> 4 files changed, 796 insertions(+), 7 deletions(-) >>> >>> diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h >>> index 73bfc20..bc119f8 100644 >>> --- a/target-s390x/cpu.h >>> +++ b/target-s390x/cpu.h >>> @@ -127,6 +127,8 @@ typedef struct CPUS390XState { >>> QEMUTimer *tod_timer; >>> >>> QEMUTimer *cpu_timer; >>> + >>> + void *chsc_page; >>> } CPUS390XState; >>> >>> #include "cpu-qom.h" >>> @@ -363,6 +365,91 @@ static inline unsigned s390_del_running_cpu(CPUS390XState *env) >>> void cpu_lock(void); >>> void cpu_unlock(void); >>> >>> +typedef struct SubchDev SubchDev; >>> +typedef struct SCHIB SCHIB; >>> +typedef struct ORB ORB; >>> + >>> +static inline SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid, >>> + uint16_t schid) >>> +{ >>> + return NULL; >>> +} >>> +static inline bool css_subch_visible(SubchDev *sch) >>> +{ >>> + return false; >>> +} >>> +static inline void css_conditional_io_interrupt(SubchDev *sch) >>> +{ >>> +} >>> +static inline int css_do_stsch(SubchDev *sch, uint64_t addr) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline bool css_schid_final(uint8_t cssid, uint8_t ssid, uint16_t schid) >>> +{ >>> + return true; >>> +} >>> +static inline int css_do_msch(SubchDev *sch, SCHIB *schib) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_xsch(SubchDev *sch) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_csch(SubchDev *sch) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_hsch(SubchDev *sch) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_ssch(SubchDev *sch, ORB *orb) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_tsch(SubchDev *sch, uint64_t addr) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_stcrw(uint64_t addr) >>> +{ >>> + return 1; >>> +} >>> +static inline int css_do_tpi(uint64_t addr, int lowcore) >>> +{ >>> + return 0; >>> +} >>> +static inline int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid, >>> + int rfmt, uint8_t l_chpid, void *buf) >>> +{ >>> + return 0; >>> +} >>> +static inline void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo) >>> +{ >>> +} >>> +static inline int css_enable_mss(void) >>> +{ >>> + return -EINVAL; >>> +} >>> +static inline int css_enable_mcsse(void) >>> +{ >>> + return -EINVAL; >>> +} >>> +static inline int css_do_rsch(SubchDev *sch) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline int css_do_rchp(uint8_t cssid, uint8_t chpid) >>> +{ >>> + return -ENODEV; >>> +} >>> +static inline bool css_present(uint8_t cssid) >>> +{ >>> + return false; >>> +} >>> + >>> static inline void cpu_set_tls(CPUS390XState *env, target_ulong newtls) >>> { >>> env->aregs[0] = newtls >> 32; >>> diff --git a/target-s390x/ioinst.c b/target-s390x/ioinst.c >>> index 8577b2c..60ce985 100644 >>> --- a/target-s390x/ioinst.c >>> +++ b/target-s390x/ioinst.c >>> @@ -15,14 +15,19 @@ >>> >>> #include "cpu.h" >>> #include "ioinst.h" >>> +#include "trace.h" >>> >>> -#ifdef DEBUG_IOINST >>> -#define dprintf(fmt, ...) \ >>> - do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0) >>> -#else >>> -#define dprintf(fmt, ...) \ >>> - do { } while (0) >>> -#endif >>> +/* Special handling for the prefix page. */ >>> +static void *s390_get_address(CPUS390XState *env, ram_addr_t guest_addr) >>> +{ >>> + if (guest_addr < 8192) { >>> + guest_addr += env->psa; >>> + } else if ((env->psa <= guest_addr) && (guest_addr < env->psa + 8192)) { >>> + guest_addr -= env->psa; >>> + } >>> + >>> + return qemu_get_ram_ptr(guest_addr); >> >> Do we actually need this? > > Yes. I've seen failures for I/O instructions using the lowcore (which > the Linux kernel likes to do). Then we want an s390 generic function that does this, not an io specific one though, right? Also qemu_get_ram_ptr is a no-go, as it doesn't do boundary checks. So what we really want is something like s390_cpu_physical_memory_map(env, ...) with a special case on the lowcore. > >> >>> +} >>> >>> int ioinst_disassemble_sch_ident(uint32_t value, int *m, int *cssid, int *ssid, >>> int *schid) >>> @@ -44,3 +49,678 @@ int ioinst_disassemble_sch_ident(uint32_t value, int *m, int *cssid, int *ssid, >>> *schid = value & IOINST_SCHID_NR; >>> return 0; >>> } >>> + >>> +int ioinst_handle_xsch(CPUS390XState *env, uint64_t reg1) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + int ret = -ENODEV; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("xsch", cssid, ssid, schid); >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch && css_subch_visible(sch)) { >>> + ret = css_do_xsch(sch); >>> + } >>> + switch (ret) { >>> + case -ENODEV: >>> + cc = 3; >>> + break; >>> + case -EBUSY: >>> + cc = 2; >>> + break; >>> + case 0: >>> + cc = 0; >>> + break; >>> + default: >>> + cc = 1; >>> + break; >>> + } >>> + >>> + return cc; >>> +} >>> + >>> +int ioinst_handle_csch(CPUS390XState *env, uint64_t reg1) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + int ret = -ENODEV; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("csch", cssid, ssid, schid); >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch && css_subch_visible(sch)) { >>> + ret = css_do_csch(sch); >>> + } >>> + if (ret == -ENODEV) { >>> + cc = 3; >>> + } else { >>> + cc = 0; >>> + } >>> + return cc; >>> +} >>> + >>> +int ioinst_handle_hsch(CPUS390XState *env, uint64_t reg1) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + int ret = -ENODEV; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("hsch", cssid, ssid, schid); >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch && css_subch_visible(sch)) { >>> + ret = css_do_hsch(sch); >>> + } >>> + switch (ret) { >>> + case -ENODEV: >>> + cc = 3; >>> + break; >>> + case -EBUSY: >>> + cc = 2; >>> + break; >>> + case 0: >>> + cc = 0; >>> + break; >>> + default: >>> + cc = 1; >>> + break; >>> + } >>> + >>> + return cc; >>> +} >>> + >>> +static int ioinst_schib_valid(SCHIB *schib) >>> +{ >>> + if ((schib->pmcw.flags & PMCW_FLAGS_MASK_INVALID) || >>> + (schib->pmcw.chars & PMCW_CHARS_MASK_INVALID)) { >>> + return 0; >>> + } >>> + /* Disallow extended measurements for now. */ >>> + if (schib->pmcw.chars & PMCW_CHARS_MASK_XMWME) { >>> + return 0; >>> + } >>> + return 1; >>> +} >>> + >>> +int ioinst_handle_msch(CPUS390XState *env, uint64_t reg1, uint32_t ipb) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + SCHIB *schib; >>> + uint64_t addr; >>> + int ret = -ENODEV; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("msch", cssid, ssid, schid); >>> + addr = ipb >> 28; >>> + if (addr > 0) { >>> + addr = env->regs[addr]; >>> + } >>> + addr += (ipb & 0xfff0000) >> 16; >> >> This adds the upper bits twice. Are you sire that's correct? > > If addr was 0, it doesn't. If addr was > 0 before, we grabbed the > address from the corresponding register and want to add to it. This is a very confusing way of writing what you're trying to express then :). How about hwaddr addr = 0; reg = ipb >> 28; if (reg) { addr = env->regs[reg]; } addr += (ipb >> 16) & 0xfff0; > >> >>> + schib = s390_get_address(env, addr); >>> + if (!schib) { >>> + program_interrupt(env, PGM_SPECIFICATION, 2); >>> + return -EIO; >>> + } >>> + if (!ioinst_schib_valid(schib)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch && css_subch_visible(sch)) { >>> + ret = css_do_msch(sch, schib); >>> + } >>> + switch (ret) { >>> + case -ENODEV: >>> + cc = 3; >>> + break; >>> + case -EBUSY: >>> + cc = 2; >>> + break; >>> + case 0: >>> + cc = 0; >>> + break; >>> + default: >>> + cc = 1; >>> + break; >>> + } >>> + >>> + return cc; >>> +} >>> + >>> +static int ioinst_orb_valid(ORB *orb) >>> +{ >>> + if ((orb->ctrl0 & ORB_CTRL0_MASK_INVALID) || >>> + (orb->ctrl1 & ORB_CTRL1_MASK_INVALID)) { >>> + return 0; >>> + } >>> + if ((orb->cpa & 0x80000000) != 0) >> >> What is this bit's name? > > Sigh, perhaps I need more defines... > >> >>> { >>> + return 0; >>> + } >>> + return 1; >>> +} >>> + >>> +int ioinst_handle_ssch(CPUS390XState *env, uint64_t reg1, uint32_t ipb) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + ORB *orb; >>> + uint64_t addr; >>> + int ret = -ENODEV; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("ssch", cssid, ssid, schid); >>> + addr = ipb >> 28; >>> + if (addr > 0) { >>> + addr = env->regs[addr]; >>> + } >>> + addr += (ipb & 0xfff0000) >> 16; >> >> Same logic as above. Please combine. > > OK, makes sense to write a helper function for this addressing. > >> >>> + orb = s390_get_address(env, addr); >>> + if (!orb) { >>> + program_interrupt(env, PGM_SPECIFICATION, 2); >>> + return -EIO; >>> + } >>> + if (!ioinst_orb_valid(orb)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch && css_subch_visible(sch)) { >>> + ret = css_do_ssch(sch, orb); >>> + } >>> + switch (ret) { >>> + case -ENODEV: >>> + cc = 3; >>> + break; >>> + case -EBUSY: >>> + cc = 2; >>> + break; >>> + case 0: >>> + cc = 0; >>> + break; >>> + default: >>> + cc = 1; >>> + break; >>> + } >> >> In fact I've seen this one multiple times too now. Please extract the retval->cc conversion into a function. > > Hm. It's somewhat generic (as in use for several instructions), but not > completely generic. Will think about it. > >> >>> + >>> + return cc; >>> +} >>> + >>> +int ioinst_handle_stcrw(CPUS390XState *env, uint32_t ipb) >>> +{ >>> + CRW *crw; >>> + uint64_t addr; >>> + int cc; >>> + >>> + addr = ipb >> 28; >>> + if (addr > 0) { >>> + addr = env->regs[addr]; >>> + } >>> + addr += (ipb & 0xfff0000) >> 16; >>> + crw = s390_get_address(env, addr); >>> + if (!crw) { >>> + program_interrupt(env, PGM_SPECIFICATION, 2); >>> + return -EIO; >>> + } >>> + if (addr < 8192) { >>> + addr += env->psa; >>> + } else if ((env->psa <= addr) && (addr < env->psa + 8192)) { >>> + addr -= env->psa; >>> + } >> >> Eh :) > > Hm... > >> >>> + cc = css_do_stcrw(addr); >>> + /* 0 - crw stored, 1 - zeroes stored */ >>> + return cc; >>> +} >>> + >>> +int ioinst_handle_stsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + uint64_t addr; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("stsch", cssid, ssid, schid); >>> + addr = ipb >> 28; >>> + if (addr > 0) { >>> + addr = env->regs[addr]; >>> + } >>> + addr += (ipb & 0xfff0000) >> 16; >>> + if (addr < 8192) { >>> + addr += env->psa; >>> + } else if ((env->psa <= addr) && (addr < env->psa + 8192)) { >>> + addr -= env->psa; >>> + } >>> + if (!qemu_get_ram_ptr(addr)) { >>> + program_interrupt(env, PGM_SPECIFICATION, 2); >>> + return -EIO; >>> + } >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch) { >>> + if (css_subch_visible(sch)) { >>> + css_do_stsch(sch, addr); >>> + cc = 0; >>> + } else { >>> + /* Indicate no more subchannels in this css/ss */ >>> + cc = 3; >>> + } >>> + } else { >>> + if (css_schid_final(cssid, ssid, schid)) { >>> + cc = 3; /* No more subchannels in this css/ss */ >>> + } else { >>> + int i; >>> + >>> + /* Store an empty schib. */ >>> + for (i = 0; i < sizeof(SCHIB); i++) { >>> + stb_phys(addr + i, 0); >>> + } >>> + cc = 0; >>> + } >>> + } >>> + return cc; >>> +} >>> + >>> +int ioinst_handle_tsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb) >>> +{ >>> + int cssid, ssid, schid, m; >>> + SubchDev *sch; >>> + IRB *irb; >>> + uint64_t addr; >>> + int ret = -ENODEV; >>> + int cc; >>> + >>> + if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) { >>> + program_interrupt(env, PGM_OPERAND, 2); >>> + return -EIO; >>> + } >>> + trace_ioinst_sch_id("tsch", cssid, ssid, schid); >>> + addr = ipb >> 28; >>> + if (addr > 0) { >>> + addr = env->regs[addr]; >>> + } >>> + addr += (ipb & 0xfff0000) >> 16; >>> + irb = s390_get_address(env, addr); >>> + if (!irb) { >>> + program_interrupt(env, PGM_SPECIFICATION, 2); >>> + return -EIO; >>> + } >>> + sch = css_find_subch(m, cssid, ssid, schid); >>> + if (sch && css_subch_visible(sch)) { >>> + if (addr < 8192) { >>> + addr += env->psa; >>> + } else if ((env->psa <= addr) && (addr < env->psa + 8192)) { >>> + addr -= env->psa; >>> + } >>> + ret = css_do_tsch(sch, addr); >>> + /* 0 - status pending, 1 - not status pending */ >>> + cc = ret; >>> + } else { >>> + cc = 3; >>> + } >>> + return cc; >>> +} >>> + >>> +typedef struct ChscReq { >>> + uint16_t len; >>> + uint16_t command; >>> + uint32_t param0; >>> + uint32_t param1; >>> + uint32_t param2; >>> +} QEMU_PACKED ChscReq; >>> + >>> +typedef struct ChscResp { >>> + uint16_t len; >>> + uint16_t code; >>> + uint32_t param; >>> + char data[0]; >>> +} QEMU_PACKED ChscResp; >>> + >>> +#define CHSC_SCPD 0x0002 >>> +#define CHSC_SCSC 0x0010 >>> +#define CHSC_SDA 0x0031 >>> + >>> +static void ioinst_handle_chsc_scpd(ChscReq *req, ChscResp *res) >>> +{ >>> + uint16_t resp_code; >>> + int rfmt; >>> + uint16_t cssid; >>> + uint8_t f_chpid, l_chpid; >>> + int desc_size; >>> + int m; >>> + >>> + rfmt = (req->param0 & 0x00000f00) >> 8; >>> + if ((rfmt == 0) || (rfmt == 1)) { >>> + rfmt = (req->param0 & 0x10000000) >> 28; >> >> Too many magic numbers. > > I can replace them with a slew of one-use magic defines... Yes, please. We have a lot of code in QEMU with logic like the one above, where the meaning is "this bit sets a mode we don't support, so abort now". I want to make sure that whoever reads this code knows why checks are the way they are. > >> >>> + } >>> + if ((req->len != 0x0010) || (req->param0 & 0xc000f000) || >>> + (req->param1 & 0xffffff00) || req->param2) { >>> + resp_code = 0x0003; >>> + goto out_err; >>> + } >>> + if (req->param0 & 0x0f000000) { >>> + resp_code = 0x0007; >>> + goto out_err; >>> + } >>> + cssid = (req->param0 & 0x00ff0000) >> 16; >>> + m = req->param0 & 0x20000000; >>> + if (cssid != 0) { >>> + if (!m || !css_present(cssid)) { >>> + resp_code = 0x0008; >>> + goto out_err; >>> + } >>> + } >>> + f_chpid = req->param0 & 0x000000ff; >>> + l_chpid = req->param1 & 0x000000ff; >>> + if (l_chpid < f_chpid) { >>> + resp_code = 0x0003; >>> + goto out_err; >>> + } >>> + desc_size = css_collect_chp_desc(m, cssid, f_chpid, l_chpid, rfmt, >>> + &res->data); >>> + res->code = 0x0001; >>> + res->len = 8 + desc_size; >>> + res->param = rfmt; >>> + return; >>> + >>> + out_err: >>> + res->code = resp_code; >>> + res->len = 8; >>> + res->param = rfmt; >>> +} >>> + >>> +static void ioinst_handle_chsc_scsc(ChscReq *req, ChscResp *res) >>> +{ >>> + uint8_t cssid; >>> + uint16_t resp_code; >>> + uint32_t general_chars[510]; >>> + uint32_t chsc_chars[508]; >>> + >>> + if (req->param0 & 0x000f0000) { >>> + resp_code = 0x0007; >>> + goto out_err; >>> + } >>> + cssid = (req->param0 & 0x0000ff00) >> 8; >>> + if (cssid != 0) { >>> + if (!(req->param0 & 0x20000000) || !css_present(cssid)) { >>> + resp_code = 0x0008; >>> + goto out_err; >>> + } >>> + } >>> + if ((req->param0 & 0xdff000ff) || req->param1 || req->param2) { >>> + resp_code = 0x0003; >>> + goto out_err; >>> + } >>> + res->code = 0x0001; >>> + res->len = 4080; >>> + res->param = 0; >>> + >>> + memset(general_chars, 0, sizeof(general_chars)); >>> + memset(chsc_chars, 0, sizeof(chsc_chars)); >>> + >>> + general_chars[0] = 0x03000000; >>> + general_chars[1] = 0x00059000; >>> + >>> + chsc_chars[0] = 0x40000000; >>> + chsc_chars[3] = 0x00040000; >>> + >>> + memcpy(res->data, general_chars, sizeof(general_chars)); >>> + memcpy(res->data + sizeof(general_chars), chsc_chars, sizeof(chsc_chars)); >>> + return; >>> + >>> + out_err: >>> + res->code = resp_code; >>> + res->len = 8; >>> + res->param = 0; >>> +} >>> + >>> +#define CHSC_SDA_OC_MCSSE 0x0 >>> +#define CHSC_SDA_OC_MSS 0x2 >>> +static void ioinst_handle_chsc_sda(ChscReq *req, ChscResp *res) >>> +{ >>> + uint16_t resp_code = 0x0001; >>> + uint16_t oc; >>> + int ret; >>> + >>> + if ((req->len != 0x0400) || (req->param0 & 0xf0ff0000)) { >>> + resp_code = 0x0003; >>> + goto out; >>> + } >>> + >>> + if (req->param0 & 0x0f000000) { >>> + resp_code = 0x0007; >>> + goto out; >>> + } >>> + >>> + oc = req->param0 & 0x0000ffff; >>> + switch (oc) { >>> + case CHSC_SDA_OC_MCSSE: >>> + ret = css_enable_mcsse(); >>> + if (ret == -EINVAL) { >>> + resp_code = 0x0101; >>> + goto out; >>> + } >>> + break; >>> + case CHSC_SDA_OC_MSS: >>> + ret = css_enable_mss(); >>> + if (ret == -EINVAL) { >>> + resp_code = 0x0101; >>> + goto out; >>> + } >>> + break; >>> + default: >>> + resp_code = 0x0003; >>> + goto out; >>> + } >>> + >>> +out: >>> + res->code = resp_code; >>> + res->len = 8; >>> + res->param = 0; >>> +} >>> + >>> +static void ioinst_handle_chsc_unimplemented(ChscResp *res) >>> +{ >>> + res->len = 8; >>> + res->code = 0x0004; >>> + res->param = 0; >>> +} >>> + >>> +int ioinst_handle_chsc(CPUS390XState *env, uint32_t ipb) >>> +{ >>> + ChscReq *req; >>> + ChscResp *res; >>> + uint64_t addr; >>> + int reg; >>> + >>> + trace_ioinst("chsc"); >>> + reg = (ipb >> 20) & 0x00f; >>> + addr = env->regs[reg]; >>> + req = s390_get_address(env, addr); >>> + if (!req) { >>> + program_interrupt(env, PGM_SPECIFICATION, 2); >>> + return -EIO; >>> + } >>> + if (!env->chsc_page) { >>> + env->chsc_page = g_malloc0(TARGET_PAGE_SIZE); >> >> Just make it an actual part of the struct, no need for the extra allocation. > > Is having an extra page per cpu by default fine? If yes, I can do so. Yes, definitely :). This is user space, so untouched memory is never really allocated. Alex -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html