From owner-svn-src-all@freebsd.org Thu Oct 17 23:17:58 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 27EA015FD84; Thu, 17 Oct 2019 23:17:58 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 46vQ7T703gz3MBM; Thu, 17 Oct 2019 23:17:57 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id CEE9527D7D; Thu, 17 Oct 2019 23:17:57 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x9HNHvqe029799; Thu, 17 Oct 2019 23:17:57 GMT (envelope-from jhb@FreeBSD.org) Received: (from jhb@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x9HNHvUo029796; Thu, 17 Oct 2019 23:17:57 GMT (envelope-from jhb@FreeBSD.org) Message-Id: <201910172317.x9HNHvUo029796@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: jhb set sender to jhb@FreeBSD.org using -f From: John Baldwin Date: Thu, 17 Oct 2019 23:17:57 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r353703 - stable/12/usr.sbin/bhyve X-SVN-Group: stable-12 X-SVN-Commit-Author: jhb X-SVN-Commit-Paths: stable/12/usr.sbin/bhyve X-SVN-Commit-Revision: 353703 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Oct 2019 23:17:58 -0000 Author: jhb Date: Thu Oct 17 23:17:56 2019 New Revision: 353703 URL: https://svnweb.freebsd.org/changeset/base/353703 Log: MFC 348212,348712: Add support for writing to guest memory in the debug server. 348212: Add support for writing to guest memory in the debug server. - Add a write_mem counterpart to read_mem to handle writes to MMIO. - Add support for the GDB 'M' packet to write bytes to the guest's memory. For MMIO writes, attempt to batch writes up into words. This is imprecise, but if you write a single 2 or 4-byte aligned word, it should be treated as a single MMIO write operation. - While here, tidy up the parsing of the 'm' command used for reading memory to match 'M'. 348712: Use parse_integer to avoid sign extension. Coverity warned about gdb_write_mem sign extending the result of parse_byte shifted left by 24 bits when generating a 32-bit memory write value for MMIO. Simplify the code by using parse_integer instead of unrolled parse_byte calls. Modified: stable/12/usr.sbin/bhyve/gdb.c stable/12/usr.sbin/bhyve/mem.c stable/12/usr.sbin/bhyve/mem.h Directory Properties: stable/12/ (props changed) Modified: stable/12/usr.sbin/bhyve/gdb.c ============================================================================== --- stable/12/usr.sbin/bhyve/gdb.c Thu Oct 17 22:37:25 2019 (r353702) +++ stable/12/usr.sbin/bhyve/gdb.c Thu Oct 17 23:17:56 2019 (r353703) @@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$"); #ifndef WITHOUT_CAPSICUM #include #endif +#include #include #include #include @@ -768,15 +769,24 @@ gdb_read_mem(const uint8_t *data, size_t len) bool started; int error; + /* Skip 'm' */ + data += 1; + len -= 1; + + /* Parse and consume address. */ cp = memchr(data, ',', len); - if (cp == NULL) { + if (cp == NULL || cp == data) { send_error(EINVAL); return; } - gva = parse_integer(data + 1, cp - (data + 1)); - resid = parse_integer(cp + 1, len - (cp + 1 - data)); - started = false; + gva = parse_integer(data, cp - data); + len -= (cp - data) + 1; + data += (cp - data) + 1; + /* Parse length. */ + resid = parse_integer(data, len); + + started = false; while (resid > 0) { error = guest_vaddr2paddr(cur_vcpu, gva, &gpa); if (error == -1) { @@ -862,6 +872,115 @@ gdb_read_mem(const uint8_t *data, size_t len) finish_packet(); } +static void +gdb_write_mem(const uint8_t *data, size_t len) +{ + uint64_t gpa, gva, val; + uint8_t *cp; + size_t resid, todo, bytes; + int error; + + /* Skip 'M' */ + data += 1; + len -= 1; + + /* Parse and consume address. */ + cp = memchr(data, ',', len); + if (cp == NULL || cp == data) { + send_error(EINVAL); + return; + } + gva = parse_integer(data, cp - data); + len -= (cp - data) + 1; + data += (cp - data) + 1; + + /* Parse and consume length. */ + cp = memchr(data, ':', len); + if (cp == NULL || cp == data) { + send_error(EINVAL); + return; + } + resid = parse_integer(data, cp - data); + len -= (cp - data) + 1; + data += (cp - data) + 1; + + /* Verify the available bytes match the length. */ + if (len != resid * 2) { + send_error(EINVAL); + return; + } + + while (resid > 0) { + error = guest_vaddr2paddr(cur_vcpu, gva, &gpa); + if (error == -1) { + send_error(errno); + return; + } + if (error == 0) { + send_error(EFAULT); + return; + } + + /* Write bytes to current page. */ + todo = getpagesize() - gpa % getpagesize(); + if (todo > resid) + todo = resid; + + cp = paddr_guest2host(ctx, gpa, todo); + if (cp != NULL) { + /* + * If this page is guest RAM, write it a byte + * at a time. + */ + while (todo > 0) { + assert(len >= 2); + *cp = parse_byte(data); + data += 2; + len -= 2; + cp++; + gpa++; + gva++; + resid--; + todo--; + } + } else { + /* + * If this page isn't guest RAM, try to handle + * it via MMIO. For MMIO requests, use + * aligned writes of words when possible. + */ + while (todo > 0) { + if (gpa & 1 || todo == 1) { + bytes = 1; + val = parse_byte(data); + } else if (gpa & 2 || todo == 2) { + bytes = 2; + val = be16toh(parse_integer(data, 4)); + } else { + bytes = 4; + val = be32toh(parse_integer(data, 8)); + } + error = write_mem(ctx, cur_vcpu, gpa, val, + bytes); + if (error == 0) { + gpa += bytes; + gva += bytes; + resid -= bytes; + todo -= bytes; + data += 2 * bytes; + len -= 2 * bytes; + } else { + send_error(EFAULT); + return; + } + } + } + assert(resid == 0 || gpa % getpagesize() == 0); + } + assert(len == 0); + send_ok(); +} + static bool command_equals(const uint8_t *data, size_t len, const char *cmd) { @@ -1001,6 +1120,9 @@ handle_command(const uint8_t *data, size_t len) case 'm': gdb_read_mem(data, len); break; + case 'M': + gdb_write_mem(data, len); + break; case 'T': { int tid; @@ -1036,7 +1158,6 @@ handle_command(const uint8_t *data, size_t len) finish_packet(); break; case 'G': /* TODO */ - case 'M': /* TODO */ case 'v': /* Handle 'vCont' */ /* 'vCtrlC' */ Modified: stable/12/usr.sbin/bhyve/mem.c ============================================================================== --- stable/12/usr.sbin/bhyve/mem.c Thu Oct 17 22:37:25 2019 (r353702) +++ stable/12/usr.sbin/bhyve/mem.c Thu Oct 17 23:17:56 2019 (r353703) @@ -251,30 +251,43 @@ emulate_mem(struct vmctx *ctx, int vcpu, uint64_t padd return (access_memory(ctx, vcpu, paddr, emulate_mem_cb, &ema)); } -struct read_mem_args { - uint64_t *rval; +struct rw_mem_args { + uint64_t *val; int size; + int operation; }; static int -read_mem_cb(struct vmctx *ctx, int vcpu, uint64_t paddr, struct mem_range *mr, +rw_mem_cb(struct vmctx *ctx, int vcpu, uint64_t paddr, struct mem_range *mr, void *arg) { - struct read_mem_args *rma; + struct rw_mem_args *rma; rma = arg; - return (mr->handler(ctx, vcpu, MEM_F_READ, paddr, rma->size, - rma->rval, mr->arg1, mr->arg2)); + return (mr->handler(ctx, vcpu, rma->operation, paddr, rma->size, + rma->val, mr->arg1, mr->arg2)); } int read_mem(struct vmctx *ctx, int vcpu, uint64_t gpa, uint64_t *rval, int size) { - struct read_mem_args rma; + struct rw_mem_args rma; - rma.rval = rval; + rma.val = rval; rma.size = size; - return (access_memory(ctx, vcpu, gpa, read_mem_cb, &rma)); + rma.operation = MEM_F_READ; + return (access_memory(ctx, vcpu, gpa, rw_mem_cb, &rma)); +} + +int +write_mem(struct vmctx *ctx, int vcpu, uint64_t gpa, uint64_t wval, int size) +{ + struct rw_mem_args rma; + + rma.val = &wval; + rma.size = size; + rma.operation = MEM_F_WRITE; + return (access_memory(ctx, vcpu, gpa, rw_mem_cb, &rma)); } static int Modified: stable/12/usr.sbin/bhyve/mem.h ============================================================================== --- stable/12/usr.sbin/bhyve/mem.h Thu Oct 17 22:37:25 2019 (r353702) +++ stable/12/usr.sbin/bhyve/mem.h Thu Oct 17 23:17:56 2019 (r353703) @@ -61,5 +61,7 @@ int read_mem(struct vmctx *ctx, int vcpu, uint64_t gpa int register_mem(struct mem_range *memp); int register_mem_fallback(struct mem_range *memp); int unregister_mem(struct mem_range *memp); +int write_mem(struct vmctx *ctx, int vcpu, uint64_t gpa, uint64_t wval, + int size); #endif /* _MEM_H_ */